Longtime federal prosecutor Halsey Frank has been nominated by President Donald Trump to serve as U.S. attorney for Maine, U.S. Sen. Susan Collins announced Thursday.

Collins said that she would work for Frank’s swift confirmation in the Senate.

“Halsey is an intelligent, highly competent, experienced law enforcement professional, and I am delighted that he has been nominated,” she said in a press release. “With 30 years of experience working for the U.S. Department of Justice in both Washington, D.C., and Maine, he is very well qualified to assume this crucial position.”

If confirmed, Frank would succeed Thomas E. Delahanty II, who left the position in March.

Frank, of Portland, has served as an assistant U.S. attorney for 17 years. Prior to his current post, he worked as a federal prosecutor for the District of Columbia.

He recently prosecuted Sidney Kilmartin, 54, of South Windham who was found guilty in October of mailing cyanide to an Englishman who used it to commit suicide.

Frank is a graduate of Boston University School of Law and Wesleyan University.