A helicopter searching for dozens of rebel-held hostages in Peru’s Amazon jungle was attacked with gunfire Thursday and a police captain on board was killed and three people were wounded, including the pilot, the Interior Ministry said.

The attack came as the government sent 1,500 soldiers and police to the area near Peru’s key Camisea gas field to try to rescue 40 construction workers who were grabbed on Monday by Maoist Shining Path guerrillas. Officials say the rebels have demanded $10 million in ransom.

Gunfire from a group of rebels tore through the helicopter as it was patrolling an area of lakes in the Echarate district, and police Capt. Nancy Flores died, the Interior Ministry said in a statement. It said the pilot, a police technician and a civilian suffered wounds. Those on board the helicopter were part of the recently deployed force.

Mayor Fedia Castro of Convencion municipality, which includes the town where the workers were abducted, told the radio station Radioprogramas that the civilian wounded on the helicopter was working as a guide.

President Ollanta Humala urged the hostages’ families to trust in the authorities, and he vowed to capture and prosecute the kidnappers.

“We hope that in a very short time we can resolve the problem, aiming for the cost to be zero,’’ Humala told reporters before news of the shooting emerged.

Local officials have said the workers were kidnapped in the hamlet of Kepashiato, near the country’s main natural gas field in the Amazon jungle. Those who were abducted were working as contractors on gas industry projects.

“The government doesn’t negotiate with terrorists,’’ Justice Minister Juan Jimenez said Thursday in an interview with Panamericana Television.

The Defense Ministry said in a statement Wednesday night that 1,500 soldiers and police were involved in the search and rescue operation.