US authorities investigating possible scenarios of failed attempt

U.S. authorities are investigating a thwarted car bombing in New York's famed Times Square where thousands of people gather each day and night to eat, drink and shop. As yet authorities have only described it as a potential act of terrorism and have not identified a suspect or motive.

Times Square has always been believed to be a target for attack and, in addition to being a major tourist destination, its buildings are occupied by big corporate names, major news and television outlets and the Nasdaq Stock Market.

Following are scenarios for who may have been responsible for the failed attempt.


FOREIGN MILITANTS

Authorities will likely try to determine whether the attack was sponsored by foreign militants such as al Qaeda or offshoots of the organization. That group was behind the September 11, 2001, attacks at the World Trade Center in Manhattan as well as the Pentagon.

Its members have made it clear they want to strike the United States again, including New York. While the U.S.-led forces in Afghanistan have damaged much of the al Qaeda network, the group has continued to operate and carry out attacks around the world.

In December, a young Nigerian man Umar Farouk Abdulmutallab tried but failed to blow up a U.S. commercial airliner landing in Detroit with a bomb hidden in his underwear. He told authorities after his arrest he had been trained and given the bomb materials by al Qaeda militants in Yemen.

That appeared eerily similar to another attack by Briton Richard Reid who packed explosives in his shoes and tried to ignite it on an American plane months after the September 11 attacks.

AMERICANS JOINING FOREIGN CAUSES

U.S. officials have become increasingly worried about Americans joining the causes of foreign militant groups like al Qaeda or Lashkar-e-Taiba.

Last fall, several men, including the Afghan immigrant Najibullah Zazi, were arrested after law enforcement discovered their plot to set off bombs in the New York City subway system. Already two key figures have pleaded guilty to the attempted attack, including Zazi, in which they had hoped to ignite bombs made from off-the-shelf chemicals they had purchased. Zazi admitted to receiving training from al Qaeda in Pakistan's border region of Afghanistan.

Additionally, a Chicago man was arrested in October at the airport as he was embarking to Pakistan on charges he was plotting to kill a Danish cartoonist who lampooned the Prophet Mohammed. The subsequent investigation of David Headley uncovered that he had helped scout sites in Mumbai that were attacked in 2008. Six Americans were among the 166 people killed in those attacks which have been blamed on the Islamist militant group Lashkar-e-Taiba.

Two Pennsylvania women, including Colleen LaRose who sometimes went by the pseudonym JihadJane, have been charged in connection with a plotting with unnamed foreign co-conspirators to kill a Swedish cartoonist who had lampooned the Prophet Mohammed which offended many Muslims. LaRose had boasted about her potential ability as a blond-haired American to avoid detection and scrutiny by law enforcement.

Last November, a U.S. Army major who is a Muslim born in the United States, went on a shooting rampage that killed 13 and injured dozens more at Fort Hood, Texas. It was later discovered the man, Nidal Malik Hasan, had ties to a fiery anti-American Muslim cleric now believed to be hiding in Yemen, Anwar al-Awlaki.

DOMESTIC EXTREMISTS

U.S. authorities have also worried about another attack similar to the Oklahoma City bombing in 1995 in which 168 people were killed when American right-wing extremist Timothy McVeigh detonated a truck bomb made of fertilizer and other components at a federal building. Many cities have hardened key government buildings as well as tourist sites to protect them from similar attacks.

Last month nine members of a Christian militia group were arrested on charges they had conspired to kill law enforcement officers in Michigan and then attack the subsequent funeral with an improvised explosive device. That has drawn new scrutiny on militia groups, many who have said they are mostly focused on the goal of limiting the size of U.S. government and its role in Americans' lives.