An Evanston elementary school custodian was arrested Thursday night and charged with selling crack and powder cocaine on school grounds, police said.

Robert Crayton, 27, of Skokie, was arrested at Lincolnwood Elementary School, 2600 Colfax St., on federal charges of delivery and distribution of drugs on school property.

Crayton’s arrest was the result of a four-week undercover operation between the Drug Enforcement Administration and Evanston Police Department, EPD Chief Frank Kaminski said at a Friday afternoon press conference.

The custodian allegedly made three drug transactions in the past month on school premises, including one inside a first-grade classroom, Kaminski said. The typical transaction ranged from an eighth of an ounce to a half-ounce of cocaine, or $80 to $400, Kaminski said.

According to the complaint affidavit, a confidential source working with investigators made four undercover purchases of crack cocaine from Crayton at night, three of them on school grounds.

On Oct. 7, the source met Crayton at the school and bought an eighth of an ounce of crack cocaine for $90 in his car, according to a statement from the U.S. Department of Justice that detailed the incident.

Five days later, the confidential source arranged to buy more cocaine from Crayton at the school, but Crayton changed the location of the deal to an Evanston medical facility for the elderly, the statement said.

The statement also said that on Oct. 21, officers watched through a window as the confidential source talked for about 10 minutes with Crayton in a classroom and then bought about five grams of powder cocaine for $80.

The source told agents the room was a first-grade classroom and that Crayton had gotten the drugs out of a blue duffel bag that was locked inside a cabinet in the back of the classroom.

There is no evidence that Crayton dealt drugs to students, said both Kaminski and DEA agent Timothy Ogden. Neither would comment on how long Crayton may have been selling drugs out of the school.

Kaminski said he was “especially disturbed” by Crayton’s arrest.

“We view our schools as a safe haven for our little people, a special place to grow and learn,” Kaminski said, reading from a prepared statement. “Anyone who would break the sanctity of our schools deserves the harshest of punishment and our utmost disdain.”

Lincolnwood Elementary principal Beth Sagett told The Daily that Crayton seemed “really nice” and “very helpful.”

“He knew many of the children because he cleaned the rooms,” Sagett said.

Evanston/Skokie School District 65 superintendent Hardy Ray Murphy said Crayton was hired as the night custodian in 1996 and worked the 1 p.m. to 9 p.m. shift.

“We are profoundly disappointed and disturbed,” Murphy said, calling the drug dealing “a reprehensible act.” Lincolnwood has scheduled a parents meeting for Friday night.

Murphy said when Crayton was hired, the custodian had to sign a statement pledging to abide by the school district’s drug policy. Under a policy instituted after Crayton was hired, all potential district employees are checked by an outside firm that uses electronic fingerprinting scans.

If convicted, Crayton could face up to 20 years in prison and a $250,000 fine.

The Daily’s Ben Clark contributed to this report.

Reach Alison Knezevich at [email protected].