A teenager says he is scared to go outside after he was portrayed on the internet and on the front page of the New York Post as connected to the deadly Boston Marathon bombings.

Photos of Salah Eddin Barhoum, 17, and friend Yassine Zaime were posted on websites whose users have been scouring marathon-finish-line photos for suspects.

The two were also on the Post's front Thursday with the headline: "Bag men: Feds seek these two pictured at Boston Marathon."

The Post reported later on Thursday that the pair were not considered suspects, and the FBI has since identified two other men as suspects in Monday's bombings, which killed three people and injured more than 180.

But Barhoum, a track runner at Revere High School, said he was convinced some would blame him for the bombings, no matter what.

He said he was so fearful on Thursday that he ran back to the high school after a track meet when he saw a man in a car staring at him, talking into a phone.

Barhoum's father, El Houssein Barhoum, who moved his family from Morocco five years ago, said he was worried his son would be shot and fears for his wife and two young daughters.

He said he could not go to his job as a baker in Boston.

In a statement, Col Allan, New York Post editor, said: "We stand by our story. The image was emailed to law enforcement agencies yesterday afternoon seeking information about these men, as our story reported. We did not identify them as suspects.''

The photos show Barhoum with a black Nike athletic bag, wearing a blue and black track suit.

Zaime is carrying a black backpack, wearing a white cap and black track clothes.

Men with bags at the marathon have been a focus of Internet scrutiny, because officials believe that is how the bombers carried in the explosives.

Barhoum said there are only two reasons he has been labelled a suspect: His bag and his brown skin.

In running gear

Barhoum said he was at the marathon with Zaime, a friend from the running club, hoping to run a portion of it behind the official field. They took the subway, and Barhoum's bag was for his running gear.

But the pair got the address wrong and ended up at the finish line instead of where they wanted to start the race. Barhoum said they decided to stick around to see the top runners, then left.

Barhoum said that late on Wednesday, friends started flagging the online photos and commenters started their work.

He said he was so upset, he visited police early on Thursday to clear his name. He said they advised him to restrict access to his Facebook account.

When the Post published the photo later on Thursday, a bad situation got worse, Barhoum said.

"It hurts because the person who did it must be happy right now, looking at the people who are getting blamed,'' he said. "And I'm one of them.''

The Federal Bureau of Investigation is also concerned about the online manhunt.

Rick DesLauriers, FBI chief in Boston, made clear his frustration at the proliferation of amateur sleuthing that filled the vacuum of information from real investigators until Thursday.

Unveiling photos and videos of two suspects with black backpacks, one of whom was seen placing a bag at the scene of one of the blasts, he said: "These images should be the only ones ... that the public should view to assist us.

"Other photos should not be deemed credible. They unnecessarily divert the public's attention in the wrong direction and create undue work for vital law enforcement resources."