A man’s body was discovered in the San Gabriel River near where it flows under the 405 Freeway Monday morning, according to authorities.

It’s unclear at this point how the man died or if there was any foul play involved, but homicide detectives were investigating, Long Beach police said.

The man was first spotted shortly before 11 a.m., according to Long Beach Police Department spokeswoman Jennifer De Prez.

“Upon arrival, officers located the body of an adult male on the east side of the river,” De Prez said.

Photos from the scene show the man was naked.

Police shut down the bicycle path along the east side of the river while they investigated. No further information was immediately available.