DURHAM - Police reported another attack at the city’s popular American Tobacco Trail after a jogger was assaulted about 7:30 p.m. Tuesday in the section between Otis and Fayetteville streets.

It was the sixth crime reported on the trail since May 14: four simple assaults and two robberies, according to Police Chief Jose L. Lopez.

Police have made two arrests in connection with the assaults and one in connection with a robbery, he said.

The victim said he ran past a group of four or five teenagers 12 to 16 years old. As he ran on, they assaulted him, but he was able to reach home and call the police.

The assault involved the youths “throwing things at him and tripping him,” Lopez said.

“It was simple assault,” he said, but he withheld further details.

Since January 2011, 23 incidents on the trail have been reported, including robberies, assaults and indecent exposures.

Lopez said he has increased patrols on the trail, and plainclothes officers have stationed themselves in hiding, “looking for things to occur.”

“But obviously, we can’t have an officer on every segment of 7.5 miles,” he said.

The department is buying three all-terrain vehicles for trail patrols, among other uses, and is considering installing video cameras.

“The (police are) investing a lot,” Lopez said, asking residents to help police identify the culprits. “We know there are people in this community who know who they are.”

The recent assaults appear not to have been motivated by robbery, Lopez said, rather by “mischievousness” directed at lone runners.

“There are always groups that are going to pop up, especially young kids, who are going to look for something to do that’s mischievous,” he said.

“That’s why it’s very important this community bring them forward.”

Victims in five of the six incidents have described their assailants as groups of teenagers.

According to the FBI Uniform Crime Report, there were 1,893 simple assaults in Durham County in 2011. Of this summer’s ATT incidents, five occurred near Fayetteville Street, the other farther north near Enterprise Street, where the trail divides the predominantly black Southside neighborhood from affluent, predominantly white Forest Hills.

The youths in Tuesday’s incident were described as black, but police provided no additional descriptive details such as their estimated heights, weights or clothing.

After an assault July 31, Forest Hills resident Chris McLaughlin wrote Mayor Bill Bell and the City Council asking that trail security be made a public safety priority.

“One of the jewels of the city is now nearly unusable,” McLaughlin wrote. “Something needs to be done before the only people willing to venture onto the trail are the perpetrators.”

McLaughlin, who was assaulted on the trail last December, copied the letter to his neighborhood email list.

More than 15 of his neighbors, including neighborhood association President Norris Cotton, followed with similar requests.

“Some neighbors believe recent break-ins of some neighborhood homes that border the ATT may have been a result of easy criminal access from the ATT,” Cotton wrote.

The summer incidents have prompted trail users and others to organize a rally calling for greater safety on the trail, with a date and time still to be set.

Asked about safety on the American Tobacco Trail at Monday’s City Council meeting, Lopez said thousands of runners, cyclists and walkers use the trail safely every day. He repeated that point Wednesday, while acknowledging that the recent “unfortunate incidents … would be very traumatic to anyone that would be victimized.”

On Monday and again Wednesday, Lopez recommended against anyone going on the trail alone, but more because of a possible medical emergency or accident than for security.

He also advised against using the trail at dusk.

“When it’s starting to get dark, it’s not a time to be on any trail in the United States,” he said.

And he urged citizens to communicate with police.

“We really do need the community,” he said. “If you do see a group that looks suspicious – and there shouldn’t be any groups on the trail – if you see one, you should call the police.”