District police have sent a message to the men who frequent prostitutes in downtown D.C.: Don't do it, or you'll be arrested.

In two separate six-hour periods, District police arrested 54 men on prostitution solicitation-related charges. Inspector Brian Bray said he was "surprised" by the haul of "johns," particularly because word typically gets out that police are cracking down. But the customers kept coming after the first night of enforcement on Thursday, and more arrests were made overnight Friday, he said.

"This was a very large operation in terms of the number of people arrested," Bray said on Monday. "I was actually surprised myself."

Bray wouldn't release any of the names of those arrested -- they will become public when they have court dates later this month -- but said Monday that "none of them are famous." The men face up to 180 days in jail and a $1,000 fine, although Bray said most first-time offenders will be sent to a program to help them cope with their sexual desires.

Police also said they arrested 14 women on prostitution-related charges, four men on pandering charges for allegedly trying to coax undercover female officers into working for them as hookers, and two men on robbery charges for allegedly trying to rip off female undercover officers who were posing as prostitutes.

"The majority of the operation was focused on the customer side," Bray said on Monday. "We hope that if we do that there will be no customers and prostitution in the city will not be as prevalent."

Bray said police used a number of tactics to catch customers in the act, including posting advertisements on the website Backpage.com and in the Washington City Paper. Police targeted the area around 11th, 12th and K streets Northwest, Bray said. Those areas have long histories as places where prostitutes and pimps gather to sell their wares. Nearby hotels assisted police in the sting operations.

Last year, The Washington Examiner reported how a pimp pleaded guilty to prostituting a group of girls age 12 to 16 in downtown D.C. It was revealed in court documents that one of the girls was his foster child. Police caught Shelby Lewis after arresting the girls near 14th and K streets Northwest.

"We're also looking for human trafficking victims," Bray said. "We want to ID traffickers and pimps who try to trap victims."