A man who admitted plotting to detonate bombs in New York has implicated a senior al Qaeda figure in the plan, a federal law enforcement official told CNN Wednesday.

Najibullah Zazi, who pleaded guilty to a conspiracy charge in February, says Adnan Shukrijumah was at an al Qaeda camp when Zazi was overseas being trained for his mission, according to the official.

It remains unclear to investigators whether Shukrijumah directed Zazi in the plot, the official said, but Zazi told investigators he knew who Shukrijumah was.

Shukrijumah has eluded U.S. authorities for years. He lived in the United States as a teenager and young adult.

Zazi has been co-operating with authorities since pleading guilty to last fall's terror plot to blow up New York subways. Another defendant, Zarein Ahmedzay, also has pleaded guilty, while a third, Adis Medunjanin, has entered a not guilty plea.