WINDSOR, ONT. -- A search was underway by Detroit police and U.S. coast guard Wednesday for a man they believe may have fallen into the Detroit River.

Windsor police officers responded to the riverfront for a report of a marine emergency around 5:10 p.m. after a witness reported a male walking on the Detroit River. Police say he has not been seen since.

The call was determined to have taken place in the U.S. and local police are not the lead agency on the matter.

Detroit police’s air unit, harbor unit were searching the waters. Heavy Windsor police presence are seen on the Canadian site of the River.

Detroit police told CTV News around 7:45 p.m. the U.S. coast guard called off the search and rescue mission for Wednesday evening.

They say all options have been exhausted and the man has not been found.

No word yet on when the search will resume.

detroit river rescue