Federal, state, and local authorities are pledging a “worldwide” manhunt to find those responsible for detonating two bombs near the finish line of the Boston Marathon Monday afternoon.
“This is still a very active investigation,” said Rick DesLauriers, the FBI special agent in charge of the probe, during a press conference Tuesday morning. “This investigation will not be confined to Boston. This will be a world-wide investigation. We will go to the ends of the earth.”
DesLauriers declined to reveal any information on suspects, or comment on any evidence that has been collected so far in connection with the deadly attack.
Boston Police Commissioner Edward Davis said 176 people were injured in the blasts. Three people were killed and 17 are in critical condition.
Dr. George Velmahos, chief of trauma surgery at Massachusetts General Hospital, said many of the victims brought to the Boston facility “have severe wounds, many to the lower parts of their bodies,” and many of those people were injured by shrapnel, with some patients having “10, 20, 30 objects in their bodies, or more."
“There was a variety of sharp objects,” Velmahos added. “Probably these bombs had multiple metallic fragments in them. We removed pellets and nails.”
While he said doctors can't be “exactly sure” the bombs were filled with shrapnel, the metallic items being removed are very similar, meaning they may not have come from the environment around them.
Most of the injuries are to the patients' lower extremities, Velmahos said, because the bombs were low to the ground.
Doctors at Boston General have already performed amputations on four of the victims, he said, and two more have limbs that are at risk.
DesLauriers said there are “no known additional threats,” in the Boston area at this time, but he and local officials cautioned the city residents to be vigilant and cooperative with the continuing investigation.
The Joint Terrorism Task Force and the FBI have received numerous tips, he added, and he encouraged the public to continue providing any information that might be helpful.
Gene Marquez, an agent with the Bureau of Alcohol, Tobacco, Firearms, and Explosives, disputed rumors that there were seven different devices placed around Boston.
“That is not true,” he said, adding that there were "only two packages" that were placed at the marathon finish line. He said several other suspicious items were investigated, but none were explosive.
Davis noted that his officers had secured “the most complex crime scene in the history of our department,” and he said offers of assistance have come from Chicago, Los Angeles, and New York City.
On Monday, the crime scene encompassed about 15 blocks, and now it has been tightened to about 12 blocks. “We want to open up as many streets as quickly as we can," he said.
U.S. Attorney Carmen Ortiz in Boston said she has been in touch with U.S. Attorney General Eric Holder "and he has pledged all resources from the federal government. We will get to the bottom of who did this and why," she added.
Meanwhile, Boston residents can expect an increased police presence, said Massachusetts State Police Superintendent Timothy Alben.
“You'll see more troopers, a significant presence, for the comfort of the public,” Alben said.
“You'll also see enhanced security at Logan (International) Airport.”
He encouraged people who have photos or video from the crime scene to come forward, no matter what they have.
“There has to be hundreds, if not thousands (of items) and they're sitting out there,” he said. “We're urging you to bring forth anything. I assure you someone will follow up on you.”
Boston Mayor Thomas Menino also urged city residents to be patient and stand strong as the investigations proceeds.
“Our city is resilient,” he said, adding, "Boston will overcome."
© 2014 Newsmax. All rights reserved.