WASHINGTON — The Canadian government said Thursday that at least one Canadian diplomat in Cuba also has been treated for hearing loss following disclosures that a group of American diplomats in Havana suffered severe hearing loss that U.S. officials believe was caused by an advanced sonic device.

Global Affairs Canada spokeswoman Brianne Maxwell said Canadian officials “are aware of unusual symptoms affecting Canadian and US diplomatic personnel and their families in Havana. The government is actively working – including with US and Cuban authorities – to ascertain the cause.”

Maxwell added that officials don’t have any reason to believe Canadian tourists and other visitors could be affected.

Canada helped broker talks between Cuba and the United States that led to restored diplomatic relations.

In the fall of 2016, a series of U.S. diplomats began suffering unexplained losses of hearing, according to officials with knowledge of the investigation into the case. Several of the diplomats were recent arrivals at the embassy, which reopened in 2015 as part of President Barack Obama’s reestablishment of diplomatic relations with Cuba.

Some of the U.S. diplomats’ symptoms were so severe they were forced to cancel their tours early and return to the United States, officials said. After months of investigation, U.S. officials concluded the diplomats had been attacked with an advanced sonic weapon that operated outside the range of audible sound.

State Department spokeswoman Heather Nauert said the U.S. retaliated by expelling two Cuban diplomats from their embassy in Washington on May 23. She did not say how many U.S. diplomats were affected.