The Trump Tower in New York. REUTERS/Carlo Allegri

WASHINGTON (Reuters) - The chairman of the U.S. House of Representatives Intelligence Committee flatly denied on Monday that there had been a wiretap on President Donald Trump’s Trump Tower in New York, but said it was possible other surveillance was used against Trump.

“Let me be clear: We know there was not a wiretap on Trump Tower. However, it’s still possible that other surveillance activities were used against President Trump and his associates,” Republican Representative Devin Nunes said in his opening statement at a hearing on Russia’s involvement in the 2016 U.S. presidential election.

Nunes said “numerous” current and former U.S. officials had leaked potentially classified information, and that his committee intended to identify them to bring them to justice.