OKLAHOMA CITY (AP) — An Oklahoma man accused of attaching an improvised explosive device to a natural gas pipeline has his first court date set for Tuesday.

FBI Special Agent Clay Simmonds said Monday that Daniel Wells Herriman, 40, of Konowa, is due in federal court in Muskogee for the hearing starting at 10 a.m.

The FBI arrested Herriman on Friday after they say he called the 911 and told the Seminole County Sheriff's Office that he placed the IED on the pipeline and wanted to surrender.

Court documents do not list an attorney for Herriman.

The FBI said Herriman admitted making the device and placing it on the pipeline Aug. 7 with a timer on it set to detonate at 2 a.m. The device did not go off and there was no damage. FBI spokesman Clay Simmonds said the agency does not yet know of a motive.

A federal complaint says the IED was discovered Wednesday on a pipeline at the Enerfin Resources substation by company workers who notified the Okfuskee County Sheriff's Office.

Enerfin is operated by Enogex, a subsidiary of Oklahoma Gas and Electric Co.

A company spokesman has said the company had received no threats.