The NYPD arrested a homegrown lone wolf terror suspect on Saturday, who is charged with plotting to use pipe bombs that he was allegedly building in his Manhattan apartment to kill U.S. troops returning from Iraq and Afghanistan, Mayor Michael Bloomberg said Sunday night. 

U.S. citizen Jose Pimentel, also known as Muhammad Yusuf, 27, was under surveillance for about a year before the police made their move at 3:30 p.m. on Saturday, storming his home after learning that he had almost finished building a pipe bomb.

The suspect was a so-called lone wolf, motivated by his own resentment of the presence of American troops in Iraq and Afghanistan, as well as inspired by Al Qaeda propaganda, Bloomberg said. He was not part of a larger conspiracy emanating from abroad. He represents exactly the kind of threat FBI Director Robert Mueller and his experts have warned about, as American military and intelligence agencies have eroded Al Qaeda's ability to launch large-scale attacks.

Bloomberg was joined by Police Commissioner Ray Kelly and Manhattan District Attorney Cy Vance in the Sunday press conference at City Hall.

Pimentel, who lived in the Washington Heights neighborhood, had allegedly identified a number of possible targets for his bomb plot, including service members returning from the Middle East, police cruisers, post offices in upper Manhattan and a police station in Bayonne, N.J. The New York Police Department learned about the alleged activity during discussions with an NYPD confidential informant.

Pimentel's alleged plan was to test the bomb he is accused of building by detonating it in a mailbox outside the city to ensure it would work, before building three more explosive devices, which he allegedly plotted to use against one or more of his possible targets, according to Kelly.

Kelly said Pimentel allegedly became an extremist al Qaeda sympathizer as a result of reading extensively about jihad on the Internet, and especially in the magazine formerly put out by Qaeda cleric Anwar al-Awlaki, who was killed in a U.S. drone attack in Yemen on Sept. 30.

He allegedly found bomb-making instructions on Inspire.com and posted them on his own extremist Web site, www.trueislam1.com. Posts on that site include ones entitled Why Usama Ibn [sic] Laden H.A Is The Leader Of The Believrs and Make A Bomb In The Kitchen Of Your Mom's Home, which led to the Inspire.com bomb-making directions, which were still available to download as of Sunday night.

Kelly said Pimentel had allegedly adopted his extremist views a number of years ago while living in Schenectady, N.Y., but that he allegedly decided to carry out the bomb plot in August. Kelly added that al-Awlaki's death caused Pimentel to speed up the bomb-making process.

He talked about changing his name to Osama Hussein to honor his heroes Osama Bin Laden and Saddam Hussein, Kelly said. Pimentel followed instructions from Anwar Al-Awlaki to buy bomb-making materials then build a bomb.

He faces 15 years to life to 25 years to life if convicted of all the charges he faces, which include one count each of criminal possession of a weapon as a crime of terrorism, conspiracy as a crime of terrorism, soliciting or providing support for an act of terrorism, criminal possession of a weapon, and conspiracy.