DETROIT — Volunteers are again being recruited and Detroit police will enforce a curfew to keep young people off the streets as part of plans to thwart arsonists over the three-day Halloween period called Angels’ Night.

More than 4,000 people volunteered last year to help patrol city streets and neighborhoods in the long-running campaign that is credited with curtailing intentionally set fires.

Detroit residents and business owners have repeatedly demonstrated their commitment to the city by joining the effort, Mayor Mike Duggan said Monday during an event to launch volunteer recruitment.

“We know as soon as we relax, that’s when you start to have problems,” Duggan said. “So nobody around here is relaxing. We’re remaining vigilant.”

The day before Halloween had historically been called Devil’s Night in Detroit. Mischief that included throwing eggs at homes and spreading toilet paper across lawns eventually was replaced with the torching of vacant homes during the 1980s. The city had more than 800 fires during the Halloween period in 1984.

As the city fought back, elected officials and neighborhood leaders began calling it Angels’ Night and urged residents to protect their homes and the streets around them.

Only 52 fires were reported last year compared to 97 in 2014.

“The police can’t be everywhere, but if we multiply our efforts, we can be in those neighborhoods,” George Preston, president of the Mohican Regent homeowners’ association, said. “We’re just going to be the eyes and ears. We’re not going to engage anyone. Our neighbors will see us out there and it’ll help them feel safer — and the wrongdoers will see us, too.”

A city curfew will require minors younger than 17 to be accompanied by a parent or legal guardian starting at 6 p.m. on Oct. 29 and 30.

Gas station customers won’t be allowed to pump fuel into portable containers from midnight on Oct. 27 to 11:59 p.m. on Oct. 31 unless it’s for out-of-gas vehicles or to run generators. Anyone buying gas in portable containers in those cases must show valid identification.