An investigation into official flight records of financier and convicted pedophile Jeffrey Epstein’s “Lolita Express” are once again dragging former President Bill Clinton into the national spotlight.

Flight logs obtained by Gawker in January 2015 put Mr. Clinton on the billionaire’s infamous jet more than a dozen times — sometimes with a woman whom federal prosecutors suspect of procuring underage sex victims for Mr. Epstein. Fox News reported Friday that records show Mr. Clinton declined Secret Service protection on at least five flights.

The network’s investigation reveals Mr. Clinton flew on the Boeing 727 “Lolita Express” 26 times, more than doubling the previously reported 11 trips.

Bill Clinton … associated with a man like Jeffrey Epstein, who everyone in New York, certainly within his inner circles, knew was a pedophile. Why would a former president associate with a man like that?” said Conchita Sarnoff of the Washington, D.C.-based nonprofit Alliance to Rescue Victims of Trafficking, Fox reported. Ms. Sarnoff also authored a book on Mr. Epstein titled “TrafficKing.”

Mr. Epstein was arrested in 2005 and signed a plea agreement in 2007 with the U.S. Attorney’s Office, accepting a single charge of soliciting prostitution. He agreed to a 30-month sentence, registered as a “Tier 1” sex offender with the U.S. Virgin Islands and paid dozens of young girls under a federal statute providing for compensation to victims of child sexual abuse.

A Clinton spokesperson did not return the network’s emails requesting comment. Martin Weinberg, Mr. Epstein’s attorney, declined multiple inquiries into the flights.

Fox News said that the U.S. Secret Service declined to answer multiple Freedom of Information Act requests on the trips.