The casualty count from Monday afternoon's two explosions near the finish line of the Boston Marathon rose to three dead and more than 140 wounded overnight, but as of Tuesday morning there are still no reported arrests after the shocking attack.
Boston police were instructed to be on the lookout for a "darker-skinned or black male" clothed in a black sweatshirt and black backpack Monday evening, CNN and other news outlets reported, but there have been no updates on whether or not that individual was found. The man attempted to enter a restricted area minutes before the blasts.
A Saudi man believed to be 20 years old was the initial focus news reports on possible suspects. The man - reportedly in the country on a student visa - was reported as acting suspiciously immediately before the bombs went off, news reports say, and is currently hospitalized.
Police were guarding his hospital room Monday night, Fox News and the New York Post reported. Law enforcement officials told The Post that the man was tackled by a bystander after running from the attacks. The man, according to The Post, is being treated for shrapnel wounds to his leg.
Al Arabiya reports that the man and another Saudi, a female exchange student whose name and age were not reported, were injured in the blasts. "The student's friend told Al Arabiya that the victim's leg was severely injured and doctors almost amputated it," says the report. "She added however that a surgical procedure succeeded in saving her leg."
CBS Boston reports that two men were questioned by federal investigators in the lobby of a Revere, Mass., apartment building overnight. Several bags were removed from an apartment that may belong to the Saudi man around 2 a.m. Tuesday, the report said.
The apartment search, CNN reports, did not require a warrant because residents agreed to allow investigators in.
FBI agents also searched a suburban Boston home Monday evening, The Associated Press reports. A warrant was reportedly acquired before the search.
Throughout the afternoon and evening Monday Boston Police Commissioner Ed Davis vehemently denied that there was a suspect in custody. "We are questioning many people," Davis told reporters at a press briefing just before 6 p.m.
The two bombs went off seconds apart around 2:50 p.m. near the finish line of the famous annual race. Around 17,000 of the 27,000 runners crossed the finish line before the explosions, the AP reports. The race was immediately cancelled after the blasts.
Incredibly graphic images of the carnage were captured by the Boston Globe. One photo shows a young woman sitting dazed in a pool of blood. Other gory photos show victims with what appears to be shrapnel wounds to their legs.
"At least 25 to 30 people have at least one leg missing, or an ankle missing, or two legs missing," state trooper Roupen Bastajian told the AP.
Twenty-four-hour news coverage of the event allowed the media time to speculate about a broad range of possible motives. Possible motives for domestic anti-government extremists could include, cable TV commentators pointed out, that Monday was the deadline for filing federal taxes and that this week is the anniversary of the 1993 Waco, Texas, fire that killed 76 cult members and the 1995 Oklahoma City bombing that killed 168.
It's also possible that the explosions were the work of Islamic terrorists, media reports pointed out.
In the confused aftermath of the bombings, several news outlets reported that many unexploded devices were found by police. Reports still differ on whether or not there were unexploded devices. CNN cites U.S. Rep. Bill Keating, D-Mass., as saying authorities found two small, unexploded bombs.
Among the three dead victims are an 8-eight-year-old boy, according to multiple news reports that cite Boston police. The FBI has assumed control of the investigation.