FBI Director James Comey told lawmakers at a Senate hearing Tuesday that Russian hackers had penetrated the Republican National Committee's computer records, but he called it a "limited penetration of old RNC" computer systems that were "no longer in use."

The RNC has said it did not lose data to the Russians because of its strong cybersecurity. President-elect Donald Trump has repeated that assertion, and has also said weaknesses in Democratic National Committee systems had allowed them to be hacked.

While Comey did not go into detail, he appeared to be referring to a Russian-led attack on a contractor in ­Tennessee used by the Republican committee.

Federal investigators, speaking on background, have said that a single e-mail server used by that contractor had been penetrated. But it was going out of service, and contained outdated material that the Russians probably found of little value. Comey said there was no evidence "that the current RNC" or the Trump campaign had been hacked.