Officials in the Chinese city of Hangzhou said they have sent hundreds of drones airborne in search of a leopard that has been on the loose for more than three weeks.

The case of three runaway leopards has scandalized the nation, after it emerged that the Hangzhou Safari Park did not inform the public about their escape for weeks. Two of the leopards, a male and a female, have been tracked down, while one female Amur leopard remained missing Wednesday.

The local government said Tuesday night it had deployed 1,700 personnel and 990 drones to comb surrounding areas for the big cat. It also set up infrared detectors near water sources.

Hangzhou residents are advised to stay out of the woods for now. If they encounter the leopard, they should stay calm and refrain from shouting, the Hangzhou Fuyang district government said in a statement on Weibo, a social media platform.

“You can raise both hands up and stand quietly, or slowly back away,” the statement said. “Don’t turn around and run.”

Besides being home to the safari park, Hangzhou is a high-tech hub and the site of e-commerce giant Alibaba’s headquarters.

The Hangzhou Safari Park apologized Saturday. In a statement on Weibo, it said park officials did not notify the public at first because there was little risk of attack from the leopards, which are not yet fully grown, and they feared causing panic.

“Our park has reflected deeply and we want to express our deep apologies,” it said. “We sincerely accept criticism and supervision from the public.”

Police in Hangzhou’s Fuyang district announced Monday they had detained the park’s chief executive and four other employees in connection with the incident.

At a news conference Monday, Hangzhou Vice Mayor Wang Hong said the leopards escaped April 19 because employees had flouted protocol while cleaning the enclosure. He said Hangzhou police received reports of escaped leopards May 6 and 7.

Wang said the first leopard was caught by park employees April 21 with a tranquilizer dart.

The second was taken back on Saturday. The local government said it had a wounded leg but would recover.

According to a police official at the news conference, park employees decided not to immediately report the escape because they feared it would hurt sales over the May 1 Labor Day holiday. The park welcomed 97,700 visitors over the holiday, according to the Fuyang government.

Leopards are known as notoriously elusive and solitary predators, and are most active at night.

There have been several reported sightings of the leopards this month. The Hangzhou Daily newspaper cited a 60-year-old tea farmer, surnamed Zhu, as saying he spotted one on May 1 while working at his tea plantation, halfway between the safari park and Hangzhou’s city center.

“It looked like a dog, but I saw that this dog is not the right color,” he said, according to the newspaper. “It has spots and it’s a leopard!”

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