After a recent stabbing and several cell phone muggings, police this week stepped up security on Muni lines that run through the heart of the Mission.

“Operation Safe Muni,” which began on Tuesday, places undercover police on high-crime bus lines, including the 49 Van Ness-Mission and the 14 Mission, along with four other buses.

Aboard the 49.

Aboard the 49.

“It’s an enforcement tool we are using to get compliance with the public and to stop more serious criminal activity,” said Sgt. Jim Miller, of the Ingleside police station, where the program is based.

The initiative places undercover officers on buses during high-volume times, said Miller, like late afternoon. So far, police have given out 20 citations for breaking “little rules” like fare evasion, littering and smoking, but they’re hoping, ultimately, to deter bigger crimes.

“We’re trying to kill three birds with one stone,” said Miller.

While undercover stings are new to Muni, uniformed beat cops aren’t.

The transportation agency has contracted its security services out to the city’s police department since 2001. Under the Bus Inspection Program officers are required to patrol buses between two and four times per shift, and ride for at least five blocks. About a dozen additional officers are assigned to transit security full time.

But the transportation agency and city leaders, including District 8 Supervisor Bevan Dufty, have criticized the force for failing to ensure that officers spend enough time patrolling the city’s buses.

So about two months ago a card-swiping system was enacted to electronically monitor the time police actually spend on Muni. It replaced one that relied on contact slips filled out by officers.

“I do hear from my operators that they feel a little safer now,” said Brian Gordon, a line captain and sometime driver on the 14 Mission, as he parked a vehicle in the Potrero Muni depot late Monday evening.

Riding through the Mission.

Riding through the Mission.

“But I don’t know why it’s coming now when they should have been doing it all along.”

For some, seeing police hand out citations for minor infractions brings a welcome sense of order to the city’s buses, many of which carry taggers’ scribbled marks on floors, seats, walls and windows.

“It feels more safe,” said Antonio Sanchez, who was riding the 14 Mission and is also a regular on the 49. When riders are allowed to board without paying, they don’t value the driver or his rules, said Sanchez, pointing out a man who slumped in one of the bus’s window seats and drank drowsily from a 40-ounce bottle of malt liquor.

“See, that’s illegal,” he said with a shrug.

“I do feel more confident now than before,” said one 14 Mission bus driver. “When the police are on the bus people pay the fare. They give more respect to us and the passengers.”

But another driver on the 14, who asked that his name be withheld because he worried about risking his job, was skeptical.

“There wasn’t a single cop on my bus today,” he said flatly at the Muni depot Monday night. When they do ride, police “get on when the bus is empty,” he added. “They don’t ride when the bus is crowded and there are taggers in the back.”

Some riders see discrimination in the police department’s new enforcement tactics.

“It’s kind of rotten that they’re singling out the 14,” said Elaine, who declined to give her last name, as she waited for the 14 along Mission Street.

“It’s not the kind of bus that the more affluent, more vocal, more complaining people are going to ride,” she said, adding that the transportation agency needs to raise revenues and is simply targeting the “people’s bus” to do so.

Christine, who was riding the 14 Mission on Wednesday, witnessed a fare inspection sting earlier in the day that resulted in “six or 10” citations. She said she’d also seen more police on the Mission’s buses and streets in recent weeks. Still, she wasn’t fully convinced.

“It’s whatever — people are gonna do what they’re gonna do,” she said. “Like the taggers, as soon as the police get off, they’ll just start all over again.”

Pam Berry, who rode the 49 Van Ness-Mission, agreed. “We can’t go calling the cops when any little thing happens,” she said. “We have to pick up the gauntlet here and help each other.”