Russian President Vladimir Putin called President Donald Trump Sunday to thank him for a CIA tip that stopped a terrorist attack in St. Petersburg, The Washington Post reported.

Information provided by the CIA “allowed Russian law enforcement agencies to track down and detain a group of suspects who were planning to bomb the centrally located Kazan Cathedral and other crowded parts of Russia’s second-largest city,” Putin reportedly told Trump.

White House press secretary Sarah Huckabee Sanders confirmed that the call took place, according to reports.

“Based on the information the United States provided, Russian authorities were able to capture the terrorists just prior to an attack that could have killed large numbers of people,” the White House said in an announcement about the call. “Both leaders agreed that this serves as an example of the positive things that can occur when our countries work together.”

The White House did not offer details about the planned attack, but said it “could have killed large numbers of people,” Reuters reported. Neither government released the identity of the attackers.

Putin pledged to give similar tips to the U.S.

“If Russian special services obtain any information on terrorist threats against the United States and its citizens, they will definitely and immediately pass it to American counterparts through partner channels,” he reportedly said.

Although countries share intelligence, they “rarely publicly thank one another for it,” The Washington Post noted.

The two presidents also complemented each other during a conversation on Thursday. Following Putin’s annual four-hour TV news conference, he mentioned a “booming U.S. stock market as an example of Trump’s successes,” according to The Washington Post. In turn, Trump praised Putin for “acknowledging America’s strong economic performance.”