Massachusetts Governor Deval Patrick (L) speaks to the media at a shopping mall on the perimeter of a locked down area as a search for the second of two suspects wanted in the Boston Marathon bombings takes place April 19, 2013 in Watertown, Massachusetts. (Photo: AFP/Getty Images)
WASHINGTON (TheBlaze/AP) -- Massachusetts Gov. Deval Patrick on Sunday revealed more information about the crucial moments before the bombs exploded at the Boston Marathon, killing 3 and injuring at least 180.
Speaking on "Meet the Press," the governor said surveillance video from the attack shows one suspect dropping his backpack and calmly walking away before the bomb inside exploded. It clearly puts 19-year-old Dzhokhar Tsarnaev at the scene of the attack, he added.
"It does seem to be pretty clear that this suspect took the backpack off, put it down, did not react when the first explosion went off and then moved away from the backpack in time for the second explosion," Patrick remarked. "It's pretty clear about his involvement and pretty chilling, frankly."
Patrick said he hasn't actually viewed the videotape, but has been briefed by law enforcement officials about it.
Watch his entire interview, courtesy of NBC News, below:
Investigators have determined the bombs were fashioned from pressure cookers packed with explosives, nails and ball bearings and hidden in black backpacks.
Tsarnaev was captured Friday after being pulled bloody and wounded from a tarp-covered boat in a suburban Boston backyard. He is being guarded by armed officers while he recovers at a Boston hospital. He is in serious condition and hasn't been able to communicate with investigators.
His 26-year-old brother and alleged accomplice, Tamerlan, died earlier Friday after a battle with police -- and being run over by his little brother with an SUV.
The brothers are also suspected of killing an MIT police officer Thursday and severely injuring a transit officer.
"There are lots of questions about how and why," the governor concluded, and investigators will work to provide answers in the coming days and weeks.