BOSTON (AP) — The FBI has released photos of two suspects in the Boston Marathon bombings and is asking for the public's help in identifying them.

FBI Agent Richard DesLauriers says one of the suspects is believed to have planted a device outside a restaurant near the finish line of the race. He says both suspects are considered armed and extremely dangerous.

Within moments of the FBI releasing the images on its website, the agency's website crashed.

The explosions Monday killed three people and injured more than 180.

The images were released hours after President Barack Obama and first lady Michelle Obama attended an interfaith service at a Roman Catholic cathedral in Boston to remember the victims, including an 8-year-old boy.

People who were injured in the Boston Marathon bombing have had a visit today from President Barack Obama.

After he attended an interfaith church service in honor of the dead and wounded, Obama went to Massachusetts General Hospital, where he met privately with patients, their families and staff.

At the church service, Obama vowed to hunt down those responsible for the twin blasts. He said, "You will face justice."

And he said that if the bomber or bombers who struck the Boston Marathon were hoping to "intimidate" or "terrorize" Americans -- they "picked the wrong city to do it."

Like the marathoners themselves, Obama said, "We may be momentarily knocked off our feet," but that "we'll pick ourselves up."