Male pedestrian critically injured, transported to hospital, after he is struck by a car near the Stern Grove area in San Francisco.

A man walking near San Francisco's Stern Grove was critically injured when he was struck by a vehicle this morning, according to a fire official.

The man, believed to be between 20 and 30 years old, was hit around 7:35 a.m. near 20th Avenue and Wawona Street, the fire official said.

The man was transported to a hospital with life-threatening injuries, the official said.

The driver remained at the scene, she said.

The pedestrian accident comes on the same day that San Francisco police are teaming up with the California Highway Patrol to conduct an increased enforcement operation to crack down on traffic violators.

The operation kicked off for this morning's commute with a focus on Van Ness Avenue between Market and Geary streets.

For the evening commute, again more officers will be monitoring traffic on that stretch between 4 p.m. and 5:30 p.m.

From 5:30 p.m. to 7 p.m., traffic enforcement will be increased on Folsom and Essex streets near Rincon Hill.

So far this year, there have been four pedestrian traffic fatalities on Van Ness Avenue of the seven such deaths throughout the city.

The operation is an effort to reach the city's goal of zero traffic deaths by 2024, a plan the city has dubbed "Vision Zero."

As April comes to a close next week, so does National Distracted Driving Awareness Month, which aims to teach and correct dangerous driving behaviors that can lead to fatal accidents.