Police stepped up patrols Thursday on Portland’s popular Back Cove Trail, one day after a woman reported that she was sexually assaulted in a brazen daylight attack.

The 34-year-old victim told police she was walking the trail shortly after noon Wednesday when a man grabbed her near the Back Cove Trail’s half-mile marker, behind the soccer field adjacent to Interstate 295. He then forced her into an area of tall grass and raped her before fleeing.

The woman drove herself to the hospital after the assault and contacted police.

Chief Michael Sauschuck said Thursday that police are looking for two individuals who witnessed the attack and shouted in the direction of the victim and suspect, halting the assault.

“Our hope is that members of the community come forward,” the chief said. “This is an incredibly traumatic crime.”

Forcible rapes are rare in Portland, but the number reported so far this year – 18, including Wednesday’s – is on pace to eclipse the total of 21 cases in 2014.

In the past decade, rapes in Portland have ranged from a high of 42 in 2008 to a low of 21 last year. The yearly average from 2005 through 2014 was 31.5.

But Sauschuck said the overwhelming majority of those cases do not involve strangers. That, and the high-traffic location, is what makes Wednesday’s alleged attack stand out.

The suspect has been described as white, in his late 20s or early 30s, with dark hair and a goatee. He is 6 feet 1 inch to 6 feet 3 inches tall, with an average build, and he wore shiny red shorts and a black or navy blue tank top.

Sauschuck hopes the suspect’s appearance – in particular his height and distinctive shorts – might prompt people to come forward. He said anyone who was on the trail around that time Wednesday should contact police if they have information.

The chief would not comment in detail about the victim.

On Thursday morning, some trail users said they had heard about the assault and were surprised that something like that could happen, especially in daytime.

“I couldn’t believe it. There are so many people,” said Karen Leo, who lives in Jersey City, New Jersey, but often uses the trail when she visits family in Maine. “You don’t expect something like this here.”

Others were unaware of what had happened, but also were shocked.

Taylor Flood, a University of Southern Maine student who lives nearby and uses the trail regularly, said she has always felt safe there.

“My roommates tell me I should have pepper spray or a whistle,” she said. “Maybe I should. But there are so many people here on any given day.”

Lynn Marcroft, who lives nearby and walks the trail almost daily, said the incident “freaked her out.” She returned to the trail Thursday with her husband, Jim.

“It’s such a great place,” Jim Marcroft said. “People may just have to take more precautions.”

BACK COVE ASSAULTS RARE

Many walkers and runners could be seen Thursday along various sections of the 3.5-mile trail that curls around Back Cove and offers users both water and city skyline views.

Portland officers and a police dog spent Wednesday afternoon and evening collecting evidence from the scene. Detectives returned Thursday morning to continue looking for clues. At one point, a detective retrieved what appeared to be men’s underwear near the area, but it’s not known whether it was related to the assault.

Sauschuck said that in his 18 years with the Portland department, he’s aware of only two other reports of sexual assaults on Back Cove Trail. One turned out to be a false report.

Assistant Chief Vernon Malloch said he could not determine how many rapes in Portland involved strangers and how many involved people who knew each other because the department’s crime data analyst was not in the office, but he said sexual assaults by a stranger are extremely rare.

POLICE OFFER CLASSES, TIP LINES

Sauschuck understands that people are unsettled by the report of an attack.

“Crime in the city overall is down 14 percent, but that doesn’t matter to the victim (Wednesday). It doesn’t matter to me,” he said.

Portland police said Wednesday that they plan to add bicycle patrols on the trail and increase patrols on the roads around it.

They are reminding the public to carry cellphones and report any suspicious activity, and also to walk in groups if possible. If confronted by a suspicious person, be as vocal as possible to draw attention.

Police also said they have regular Rape Aggression Defense classes. The next session begins in September. Anyone seeking information can contact the department at 874-8643.

Police are asking anyone who may have seen the incident, or know of a person matching the suspect’s description, to call them at 874-8575.

Anonymous tips can be left on the department’s crime tip line, 874-8584. Cellphone users can text the keyword “Gotcha” plus their message to 274637 (CRIMES).