NEW YORK (CBSNewYork/AP) – There continue to be major ramifications and new developments following the killing of the U.S. Ambassador to Libya in a Tuesday night attack in the city of Benghazi.

All U.S. embassies around the world have been put on high alert and an elite team of 50 Marines, known as FAST (Fleet Antiterrorism Security Team) whose role is to response on short notice to terrorism threats have been dispatched to Libya’s capital, Tripoli, to guard the American embassy there.

Wednesday afternoon, high-ranking U.S. officials said there was increasing evidence and opinion that the attack that killed Ambassador Chris Stevens, 52, and three other Americans was a planned targeted attack on the anniversary of 9/11 and not a spontaneous response to a film negatively portraying the Prophet Mohammad.

President Barack Obama also delivered stern words Wednesday, saying there was “absolutely no justification for this type of senseless violence.”

“The world must stand together to unequivocally reject these brutal acts,” Obama said.

A mob with guns and rocket-propelled grenades stormed the building as Ambassador Stevens was there trying to evacuate staff when he was killed.

“We will not waver in our commitment to see that justice is done for this terrible act and make no mistake, justice will be done,” Obama said.

“How could this happen? How could this happen in a country we helped liberate, in a city we helped save from destruction,” said Secretary of State Hillary Clinton.

Speaking earlier at the State Department, Clinton said those killed had been “committed to helping the Libyan people reach for a better future.”

Earlier, Long Island Rep. Peter King expressed outraged over the “horrific, savage attack” on the U.S. consulate in Benghazi.

King, who is also the chairman of the House Committee on Homeland Security, said in a statement “that swift justice be dealt to those who perpetrated these attacks.”

Three other Americans, including foreign service information management officer Sean Smith, were also killed.

“My thoughts and prayers go out to the families of Ambassador Chris Stevens, foreign service officer Sean Smith and the two others killed in the attack,” King said. ”They were dedicated public servants working effectively to spread freedom and nurture democracy.”

The identities of the others were being withheld pending notification of next of kin.

President Obama vowed the United States would “work with the Libyan government to bring to justice” those responsible for the attacks.

Obama, who ordered an increase in security at U.S. facilities overseas, said he “condemns in the strongest possible terms the outrageous and shocking” attack.

He spoke after Republican presidential challenger Mitt Romney condemned the attack and criticized the administration for its initial response to a separate incident on Tuesday, the breach of the U.S. embassy in Cairo.

Also on Tuesday, a mob also breached the US Embassy in Cairo, protesting an obscure American-made film about Islam. The embassy released a statement condemning  the movie, drawing criticism from Romney.

“Simply put having an embassy that is has been breached and has protesters on its grounds, having violated the sovereignty for the United States and having that embassy reiterate a statement effectively apologizing for the right of free speech is not the right course for an administration,” Romney said.

Now, Romney is being criticized by people from both parties for the timing of his comments so soon after the Egypt attack and President Obama said Romney has a tendency to “shoot first and aim later.”

The White House said Obama was notified Tuesday night that Stevens was unaccounted for and was told Wednesday morning that Stevens had been killed.

Gen. Martin E. Dempsey, Gen. Martin E. Dempsey, meanwhile has called Florida preacher Terry Jones, who is known for inflammatory anti-Islamic rhetoric, to express his concerns about the aforementioned film critical of Islam, saying it could inflame tensions and trigger violence.  Dempsey has asked Jones to withdraw his support for the film.

The protests were touched off by an obscure movie made in the United States by a filmmaker who calls Islam a “cancer.” Video excerpts posted on YouTube depict the Prophet Muhammad as a fraud, a womanizer and a madman in an overtly ridiculing way, showing him having sex and calling for massacres.

In a statement, the Muslim Peace Coalition USA said it ”unequivocally condemned” the attack in Benghazi as well as attack on the U.S. embassy in Cairo, but also condemned the film.

“The makers of this film, who have willfully and deliberating [sic] incited controversy, have endangered American diplomatic personnel and troops overseas and done a gross disservice to the nation,” Dr. Shaik Ubaid, New York co-chair of MPC-USA, said in the statement. “We are a nation of free speech, and it is a core value to be defended, but we should also be a nation of responsible speech and hate speech often has dire consequences.”

Libya’s interim president, Mohammed el-Megarif, apologized for what he called the “cowardly” assault on the consulate, which also killed several Libyan security guards in the eastern city.

“We extend our apology to America, the American people and the whole world,” el-Megarif said.

Stevens is the first U.S. ambassador to be killed in an attack since 1979, when Ambassador Adolph Dubs was killed in Afghanistan.

Congressman Jim Himes (CT-4) said in a statement that he was “shocked and deeply saddened” by the attack in Libya.

He said Stevens was “instrumental in representing U.S. interests in Libya during tumultuous times, supporting the nation’s transition to democracy and adding a human touch to international relations.”

Stevens was a career diplomat who spoke Arabic and French and had already served two tours in Libya, including running the office in Benghazi during the revolt against Libyan leader Moammar Gadhafi. He was confirmed as ambassador to Libya by the Senate earlier this year.

In a statement, Rep. Nan Hayworth (NY-19) called Stevens “a man of peace” whose death “is the result of an act of heinous aggression by criminals who violate the tenets of civilized behavior as they are understood across humanity regardless of religion or ethnicity.”

His State Department biography, posted on the website of the U.S. Embassy to Libya, says he “considers himself fortunate to participate in this incredible period of change and hope for Libya.”

Clinton said Stevens had a “passion for service, for diplomacy and for the Libyan people.”

“This assignment was only the latest in his more than two decades of dedication to advancing closer ties with the people of the Middle East and North Africa which began as a Peace Corps Volunteer in Morocco,” Clinton said.

He “risked his own life to lend the Libyan people a helping hand to build the foundation for a new, free nation. He spent every day since helping to finish the work that he started,” she said.

Stevens joined the Foreign Service in 1991 and spent his early State Department career at posts in Saudi Arabia, Egypt, Syria and Israel. After working for the Senate Foreign Relations Committee staff for Sen. Richard Lugar, R-Ind., Stevens was posted to Libya as deputy chief of mission.

In that post, Stevens wrote several confidential cables back to Washington, describing Gadhafi’s bizarre behavior. During the 2011 revolt against Gadhafi, he was one of the last American diplomats to stay in Tripoli and after the embassy was closed, he was appointed to head the U.S. liaison office to the Transitional National Council.

(TM and Copyright 2012 CBS Radio Inc. and its relevant subsidiaries. CBS RADIO and EYE Logo TM and Copyright 2012 CBS Broadcasting Inc. Used under license. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed. The Associated Press contributed to this report.)

This article was published by CBS New York on September 12, 2012 and can be found here.