AP, REUTERS, CNN, NEW YORK TIMES(U.S.), BBC(UK)

Worldcrunch

WATERTOWN — Two suspects in the Boston Marathon bombing killed an MIT university police officer, injured a transit officer in a firefight and threw explosive devices at police during their getaway attempt in a long night of violence that left one of them dead and another still at large Friday morning.

Authorities said the manhunt intensified for the other suspect, a young man described as a dangerous terrorist.

The suspects were identified early Friday to The Associated Press as coming from the Russian region near Chechnya, which has been plagued by an Islamic insurgency stemming from separatist wars. A law enforcement intelligence bulletin obtained by the AP identified the surviving bomb suspect as Dzhokhar A. Tsarnaev, a 19-year-old who had been living in Cambridge, just outside Boston, and said he "may be armed and dangerous."

Boston RIC has released this flier showing at large suspect Dzhokhar A. Tsarnaev. He may be armed & dangerous. twitter.com/Suntimes/statu…

— Suntimes (@Suntimes) April 19, 2013

Officers fired at the suspects, writes CNN, wounding one of the men, possibly the person identified by the FBI as "suspect number 1," who is seen in the images released Thursday in a dark cap, sunglasses and wearing a black backpack. The man died at Beth Israel Hospital. He had bullet wounds and injuries from an explosion, according to officials. The second man was reported to have escaped on foot. During this exchange, an MBTA police officer was seriously injured and taken to the hospital, according to the New York Times.

The dramatic events overnight followed the release on Thursday by the U.S. Federal Bureau of Investigation (FBI) of pictures and video of two suspects seen wearing backpacks and baseball caps in the crowd minutes before the bombs exploded, says Reuters. On Friday the authorities effectively closed down Boston, halting transportation systems and telling people to stay home as the hunt continued.

“This situation is grave, we are here to protect public safety,” said Col. Tim Alben of the Massachusetts State Police. “We believe these are the same individuals that were responsible for the bombing on Monday at the Boston Marathon,” Mr. Alben said. “We believe that they’re responsible for the death of an MIT police officer and the shooting of an MBTA officer."

Three people were killed and more than 170 wounded when the two bombs exploded near the finish line of the Boston Marathon, writes the BBC. It was the first major terrorist attack on American soil since 9/11.