Boston police say they still have no suspects in the Boston Marathon bombing. The New York Post had reported this afternoon that authorities had found a suspect, a 20-year-old Saudi national.

"Honestly, I don't know where they're getting their information from, but it didn't come from us," a spokesperson from the Boston Police Department told TPM Livewire.

The Post had reported that the suspect was under guard at a Boston hospital after he was wounded by shrapnel in an explosion.

"At this time, we haven't been notified of any arrests or anyone apprehended," the spokesperson said.

A third explosion was confirmed by police as taking place at the JFK Library and Museum at around 4:30 p.m., though it was unclear how much damage it might have caused.

CBS News has also reported that Boston police have a surveillance video of someone bringing multiple backpacks to the blast site. 

At least 12 people have been reported dead and 50 injured as a consequence of the attacks. The Massachusetts General Hospital said it is treating at least 10 people with amputated limbs.

Boston police have shut down cell phone service in the city area as a security measure. 

"A law enforcement official says cellphone service has been shut down in the Boston area to prevent any potential remote detonations of explosives," the AP reports. "Authorities have not identified what caused the explosives that erupted at the finish line of the Boston Marathon."

Aside from the three explosions, another unexploded device was recovered.

No groups or individuals have as yet come forth to claim responsibility for the bombings.