A former congressional staffer was arrested today on federal extortion and bribery charges after allegedly taking $5,000 with promises of helping to prevent the closure of a marijuana dispensary in Compton.

Michael Kimbrew, 44, of Carson, was arrested without incident by special agents with the FBI. He pleaded not guilty, and a Los Angeles federal court judge scheduled trial for Sept. 26, according to the U.S. Attorney’s Office.

Kimbrew was a field representative for then-Rep. Janice Hahn for about a year.

Hahn—now a county supervisor—expressed surprise at the allegations.

“I’ve always trusted my employees to have the same sense of public service that I do,” she said in a prepared statement. “If these charges are true, Mr. Kimbrew abused his power as a representative of my office and violated both my trust and the trust of the public.”

Kimbrew is charged in a federal grand jury indictment returned July 21 with one count each of attempted extortion and receiving a bribe, charges which together carry a possible maximum sentence of 18 years in federal prison upon conviction.

According to the indictment, covering March through May 2015, Kimbrew approached an employee of the marijuana business, told him the store was violating the law, and said the shop would be shut down—unless the owners reached a financial agreement with him.

Kimbrew subsequently met with the dispensary’s owners inside Compton City Hall, according to the indictment, which alleges that Kimbrew claimed to be working with the FBI and could “make things happen” by ensuring the proprietors had the appropriate permits in exchange for $5,000.

According to the indictment, an undercover FBI agent posing as a business partner met with Kimbrew, who reiterated his claims that he could prevent the shutdown of the shop in exchange for $5,000. In a second meeting between Kimbrew and the undercover agent, Kimbrew allegedly accepted the $5,000 bribe.

In 2005, Kimbrew’s father, Basil, a former member of the Compton Unified School District board, pleaded no contest to misappropriation of public funds for using a school district credit card to ring up some $2,000 in charges for a personal party at a Burbank hotel. He repaid the money, and a judge sentenced him to five years probation and restricted his involvement with political campaigns or candidates.

The elder Kimbrew also pleaded no contest in November 2002 to falsifying his address to run for office. Authorities said was living in Carson when he ran for the Compton school board.