An explosive device thrown over the fence of the U.S. consulate in Nuevo Laredo, Mexico, damaged windows but caused no injuries, the office said Saturday.
The explosion occurred late Friday and authorities are investigating, a statement from the consulate said.
No other details about the blast were provided.
The agency will be closed Monday and "will reopen when we are confident that we have adequate security to keep our visitors safe," the statement said.
The incident comes less than a month after three people connected to the U.S. consulate in Ciudad Juarez were shot to death.