Updated

A man charged with plotting to blow up synagogues in New York City has pleaded guilty to state terrorism charges.

Ahmed Ferhani entered the plea on Tuesday in the unusual state-level terror case.

Manhattan state Supreme Court Justice Michael Obus says he plans to sentence Ferhani to 10 years in prison. Sentencing is set for Jan. 30.

The Manhattan district attorney's office has said Ferhani wanted to attack a synagogue. Prosecutors say he bought three guns and a grenade to do so. The buy was a sting.

His lawyers previously said Ferhani was mentally unstable. They have said the prosecution was based on insufficient evidence and dubious tactics.

Ferhani and a co-defendant were arrested last year.

A grand jury declined to indict the men on a top-level terror conspiracy charge.