A stray dog that bit 30 residents in Beijing over the weekend has been sent to the municipal agricultural administration for further tests after it was captured, a police officer said on Monday.

The dog was found in Kaiyangli community in Fengtai district by two policemen on patrol on Sunday afternoon. They asked injured residents to confirm it was the offending animal, said Liu Chunjiang, the police officer responsible for the case in Fengtai district branch of the capital's public security bureau.

"The injured people said it was the dog that bit them over the weekend after seeing the pictures we showed," he said. "Later, we sent the dog to the capital's agricultural department.

"It's a stray dog, yellow and small. Our police saw it lying on the community ground at about 5:00 pm Sunday." Liu added the dog was the one the municipal public security bureau ordered the police to search for across the city.

The dog first attacked a resident with the family name Zhang at the exit of Taoranting, a station on Beijing subway line 4 in Xicheng district, on Saturday evening. It then bit more than 20 people in other parts of the city, the bureau's official website reported.

To avoid more injuries, the bureau asked police officers in six districts, including Xicheng and Fengtai, to use monitoring devices and capture tools and search for the dog from Saturday night, the website said.

The injured were sent to a nearby hospital for rabies vaccines. Nine of them were transferred to Peking University People's Hospital for medical examination, according to the police authority.

All the injured are now fine, the police said.

According to the website, the rabies test for dogs in the city was started on May 1 and will last to the end of June. The number of dogs that have been tested has reached 200,000.

The main reason for dogs straying are demolition, abandonment and loss, the website said. Police suggested residents use dog chains when walking their pets.

If someone is bitten by a dog, they should wash the wound with water and go to hospital for a rabies vaccine as soon as possible, the police added.