Baltimore Police Department will implement a new strategy to combat illegal dirt bikes on city streets. (Kevin Richardson/The Baltimore Sun video)

Detective Hassan Rasheed had been watching the Northwest Baltimore repair shop for weeks as men brought dirt bikes in and out for repairs. Now police, intent on cracking down on illegal bikes, were prepared to move in.

Armed with a search-and-seizure warrant, Rasheed and a team of officers gathered up 16 bikes. Some had been reported stolen.

As the officers combed the West Belvedere Avenue repair shop, a crowd gathered outside the barbed-wire-topped fence.

"I'm sure everyone's [angry]," Rasheed said of the onlookers. "But these are the nuisance complaints that we get."

Police announced a new campaign this week to go after illegal dirt bikes, including offering an email address for anonymous tips about people riding or storing the vehicles.

Maj. Johnny Delgado, the commander of the Northwestern District, called the bikes and their riders a menace.

But authorities aren't relying solely on tips. Rasheed pursued his investigation for weeks. Last weekend, police narrowed Reisterstown Road near Druid Hill Park from three lanes down to one and kept tow trucks standing by to intimidate bikers from their Sunday ritual of riding in the park.

With dirt bike riding emerging as a full-fledged subculture — enthusiasts post slick videos of riding tricks on YouTube, and a documentary film about Baltimore bikers premiered at the South-by-Southwest festival in Texas — the enforcement effort has drawn mixed reactions.

At neighborhood meetings, dirt bikes are a top complaint from citizens, who call them noisy, dangerous and threatening.

Among the critics is Reuben "Peas" Maxwell, 48, who owns the property leased by the repair shop and operates his own shop next door.

He said the bikers tear up the property.

"The police don't do nothing about it," he said.

But ask the bikers and their supporters, and they say riding is a harmless outlet for young people.

Police assert that there is a relationship between dirt bike riding and more serious crimes, from drug dealing to shootings.

Riders say that's unfair.

Take Saeed Jacob. He says he's a 23-year-old who works in real estate investments in Brooklyn, N.Y. When he got word that police were seizing bikes, he rushed to the garage. He told the officers that he had all the necessary paperwork for his bike and offered to have it faxed over.

Jacob said he comes down to the city on the weekends to ride, which gives him an adrenaline rush.

"There's so many other things going on," he said. "This is trivial in comparison to what's really happening."

Standing with him was Jelani Aleong, 22, who also told the officers he had a title and registration for his $2,500 bike, but to no avail — he was told it was missing a vehicle identification number on the engine and would be taken.

"I'm a trail rider," Aleong said. "They've never caught me on no street riding."