A U.S. military helicopter carrying four people made an emergency landing Saturday afternoon on a small islet in Okinawa Prefecture but no one was injured, local authorities said.

The UH-1 chopper landed at around 4 p.m. on a sandy beach on Uruma's Ikeijima Island, according to the police. The helicopter was not heavily damaged.

According to the Okinawa Defense Bureau, overseen by the Defense Ministry, the chopper landed after a warning light came on in the cockpit. The U.S. military told the Japanese government that the pilot thus opted to make a "preventive landing."

The chopper apparently landed about 100 meters from a house, a local resident said.

The aviation incident is the latest involving U.S. aircraft in the prefecture, where opposition to the huge U.S. military presence is rife.

The island is the same one where an AH-1 attack helicopter based at U.S. Marine Corps Air Station Futenma made an emergency landing on a farm path on Jan. 20 last year.

"I'm speechless. The frequency is too often. It cannot be helped but to think there's a systemic problem within the U.S. military," Okinawa Deputy Gov. Moritake Tomikawa told reporters.

Masanori Tamaki, 61, said the chopper looked to be in trouble shortly before it landed.

"I felt it was dangerous because the helicopter was lowering altitude and heading toward the coast with a rattling noise," he said.

"The U.S. military always prioritizes military operations and neglects the anxieties of local residents," said Tamaki, who heads the local residents' association.

Ikeijima Island is about 30 km northeast of the prefectural capital Naha and is linked to Okinawa's main island by a bridge.