SAN FRANCISCO, Feb. 4 (Xinhua) -- Police increased street patrols Sunday in two urban neighborhoods in San Francisco on the U.S. west coast after they received reports of overnight sightings of mountain lions in the area, a local TV reported.

Police said a woman reported that a mountain lion was sauntering near her home late Saturday night when she drove in front of her house.

It was the second time that a mountain lion was spotted in an urban area in six months in the city.

The woman said she initially thought the animal was a dog, but a second sight showed it was a mountain lion when she drove nearer.

The big cat took off like a rocket, hopping the fence into her back yard, she told police.

The police received the second call of a mountain lion being spotted about an hour later. Police officers searched the area but failed to locate the big cat.

The police said it was not sure whether there are two separate creatures or if the same one was spotted twice.

The local TV ABC7 News Bay Area quoted local residents as saying that they were nervous about the appearance of a mountain lion in their neighborhoods, which scared them to such an extent that they even left their glass door closed.

The last mountain lion sighting in an urban neighborhood in the vicinity occurred in August last year when a resident reported an adult and a cub in a large tree near the neighborhood of the area, the police said.

An estimated 4,000 to 6,000 mountain lions are living in California, and their territory can extend from 10 to 400 square miles, or about 16 to 640 square km, according to wildlife officials.

It is not unusual for roaming animals to find themselves in populated areas. Local residents spotted pumas or mountain lions in and around San Francisco four times in June and July 2015.