BOSTON — Federal investigators said Thursday they have clear video images of two male suspects in the Boston Marathon bombings that killed three and injured 175 but they have not been able to find or identify the individuals.
Circulation of the images has been limited so far to law enforcement officials to avoid tipping off the suspects, but the video frames could be released to the public soon in an expanded effort to put names to the faces.
Officials said the individuals were considered suspects because they are seen carrying black bags at the two bomb sites 100 yards apart near the marathon's finish line area. Black remnants of duffel bags or backpacks were found by forensic experts at those same sites.
The suspects images came from the frame-by-frame scrutiny of scores of videos collected from spectators, television stations, race organizers and business security cameras of the crime scene before and after the bombings at 2:50 p.m. Monday.
In Washington, Homeland Security Secretary Janet Napolitano told a congressional committee in Washington Thursday that she wouldn't describe them as images of suspects "under technical terms." But, she added, the FBI definitely needs to talk with them and "we need the public's help in locating these individuals."
Napolitano said the federal investigation into the bombings is progressing yet it is too early to say if they are connected to a domestic or foreign terrorist plot.
"This is not an NCIS episode," she said. "Sometimes you have to take time to properly put the chain together to identiy the perpetrators, but everybody's committed to seeing that that gets done in the right way."
President Obama, who has called the bombings an act of terrorism, and his wife, Michelle, attended an interfaith healing service Thursday at Boston's Cathedral of the Holy Cross. The pews in the front of the church were filled with family and friends of the victims.