DARIEN — Four bikes were reported stolen over the course of a week from both train stations in town.

According to police, three bikes were reported stolen from the Darien Metro-North Railroad station on West Avenue and one was taken from the Noroton Heights station on Heights Road.

The first bike was stolen on Sept. 5 from the Darien Train Station. The complainant said he locked his bike to the train station bike rack around 6:15 a.m. and left it with his helmet. When he returned around 6:15 p.m., the bike, helmet and lock were gone.

On Sept. 11, the same man locked a different bike to the bike rack at the West Avenue station and left it there with his helmet. He returned around 6:15 p.m. to find his bike, lock and helmet taken again. After the second bike was stolen, the man reported both incidents to police.

The first bike was a silver, 24-speed mountain bike with black rims, worth $300. The word “gravity” was written on the frame. The second bike was a 26-inch mountain bike with a royal blue frame, valued at $110.

On Sept. 12, another complainant reported her husband’s bike had also been stolen from the West Avenue train station. According to the complaint, the woman and her husband ride their bikes to the train station every day. They locked their bikes to the rack around 7:30 a.m. that day. When the woman returned before her husband around 7:30 p.m., she found his bike missing from the rack. The lock he used was cut and left on the ground. Her bike was still on the rack.

The stolen bike was a red “Specialized” brand bike valued at $550.

On Sept. 13, a fourth theft was reported, this time from the Noroton Heights Station. The complainant left his bike locked to a rack at the station around 8 a.m. When he returned around 6:30 p.m, he found his bike was missing and his lock was cut and left on the ground. The bike was valued around $400.

According to police, the time frames and the similarities in how the bikes were taken — notably the cut locks — led them to believe the same person is responsible for all four incidents. Police said as a result they’ve been keeping a closer eye on the stations and reviewing surveillance footage from the security cameras by the platforms.

All incidents are still under investigation.

ekayata@hearstmediact.com; @erin_kayata