CRI's Xiaohong reports from Washington.

 

　　When 8-year-old Martin Richard and his 6-year-old sister stood with their mother at the finish line of the Boston Marathon, they were planning to give their father a big hug when he finished the race.

 

　　But that never happened as the deadly explosion took Martin's life and his sister's leg. Their mother underwent surgery for brain injuries.

 

　　The April 15th Boston attack left three people dead and 176 injured. Among them 17 are still in critical conditions.

 

　　Cathie Martin, professor of political science at Boston University, says she is shocked by the tragedy.

 

　　"I think everybody is pretty shocked and we tend to think this sort of thing doesn't really happen in Boston. You know, we've never had anything like this before so we're very horrified."

 

　　The bombings are now being described as an act of terrorism by President Obama, following his second national televised speech at the White House.

 

　　"This was a heinous and cowardly act. Given what we now know, the FBI is investigating is an act of terrorism."

 

　　The president stressed that officials still do not know who carried out the attack or why.

 

　　He described the investigation as being in the early stages.

 

　　Meanwhile, the authorities have disclosed some more information.

 

　　Massachusetts Governor Deval Patrick says there were only two explosive devices found at the scene. The FBI says there are "no known additional threats".

 

　　The agents have also collected pieces of nylon black bag or backpack they suspect that has been used to carry the explosives.

 

　　Authorities say high security presence in the city will continue for a few more days.

 

　　Law enforcement has also collected all film footage taken by surveillance cameras there and is urging people to submit more photos and videos they had taken at the scene.

 

　　The authorities hope such footage may provide some clues to help find those responsible.

 

　　Local reports also show that a team of bomb experts from the Navy have also joined the investigation.

 

　　The FBI has refused to disclose any more details, but is vowing to hunt worldwide for those responsible.

 

　　FBI special agent Rick Deslauriers

 

　　"This will be a worldwide investigation. We will go where the evidence and the leads take us. We will go to the ends of the Earth to identify the subject or subjects who are responsible for this despicable crime. And we will do everything we can to bring them to justice."

 

　　Boston Mayor Thomas Menino believes the city will overcome the trauma.

 

　　"This is a bad day for Boston but I think that if we pull together we'll get through it. We're a strong city. A lot of people willing to work together to make this a better place for all the people, and so, as we gather here today with all our officials, let's say Boston will overcome."

 

　　Meanwhile it's being reported local residents in Boston, including many participants of the Marathon, rushed to nearby hospitals to donate blood to assist with treatment of those injured.

 

　　Xiaohong, CRI, Washington.