An official says a high-ranking employee indicated a pressure test problem had been resolved hours before BP’s Gulf of Mexico well blew out.

Daun Winslow works for Transocean, which owns the rig that exploded April 20, killing 11 workers and setting off the Gulf spill.

Winslow tells a government panel Tuesday that there was confusion among workers in the drill shack, who were talking before the explosion about a negative pressure test, a procedure typically done before a well is plugged.

Winslow says he left while the drill team and tool pushers were discussing the pressure test to avoid disturbing them. He says the highest-ranking Transocean person on the rig later gave him a “thumbs up,” indicating it had been resolved.

Later Tuesday, BP drilling engineer Brian Morel invoked his constitutional right not to answer questions.