NAIROBI, Kenya (CNN) -- In what could be a major breakthrough in the U.S. Embassy bombing investigation, FBI agents conducted as many as five raids in Kenya this week, in cooperation with Kenyan authorities.

The searches are based in part on information reported by Mohammed Saddiq Odeh, a suspect arrested in Pakistan in connection with the bombing, sources familiar with the investigation told CNN.

Odeh was arrested in Karachi on August 7 -- the day of the bombings -- after he arrived on a flight from Nairobi. Pakistani authorities returned him to Kenya on August 16.

Since returning to Nairobi, Odeh has cooperated on a limited basis with investigators, the sources said.

The Nation newspaper reported that in one raid, large amounts of explosives were confiscated from a Nairobi hotel.

The paper reported FBI agents found 800 kilograms (1,760 pounds) of TNT in two rooms at the Hill Top Hotel which were rented by two Palestinians, a Saudi and an Egyptian from August 3 to August 7.

The August 7 bombing killed more than 247 people and injured 5,000. A simultaneous car bomb attack against the U.S. Embassy in neighboring Tanzania killed 10 people.