Police were searching for suspects Friday after a pipe bomb (search) exploded in the offices of a biotech company developing treatments for diabetes and liver disease.

The explosion early Thursday morning at Amaranth Bio Inc. (search) shattered several windows, but no injuries were reported. Police said the building had been broken into.

"It clearly was an explosive device. ... A crime was committed," said State Fire Marshal Stephen Coan, whose office was investigating the explosion, along with local police and fire departments and federal agents from the Bureau of Alcohol, Tobacco and Firearms and the FBI (search).

Coan had no comment on the possible motive for the explosion or whether there were any suspects.

On its Web site, Amaranth describes itself as an early stage biotech company whose products harness "native processes of regeneration" to produce "enough highly functional cells and tissues from one adult organ to treat thousands of patients."

The company's technology uses donated adult human tissue. Charles J. Queenan III, executive vice president of the company, said in an e-mail that the company was unaware of any threats against it or any reason to believe the company would be targeted.

"We are unaware of any likelihood, any reason or any motivation why any employee or former employee would have cause to perpetrate this act," Queenan said.

On Friday, Queenan said the company moved into the building just last month.

"[The explosion] does not appear to be directed at us as a company or anything we do," he said.

Queenan said the company would likely be able to resume full operations within weeks, though he declined to be more specific.