Two improvised explosives were thrown into the rear of the Mexican Consulate early Friday, causing small explosions that blew out some windows, authorities said. No injuries were reported.

Police believe someone on a bicycle threw the devices — made from replica grenades packed with explosive powder — at 3 a.m., New York Police Commissioner Raymond Kelly said.

The commissioner said witnesses reported seeing someone on a bike at that time near the consulate in Midtown Manhattan.

Edgar Trujillo, the press attache with the Mexican Consulate, said three windows were shattered.

Police and FBI agents were at the scene. The block was cordoned off by police tape.

In 2005, an explosion caused by two makeshift grenades fitted with fuses blew out a window near Manhattan's British consulate. There were no injuries, and no one was ever arrested in the incident.