The longtime director of Berkeley County's Emergency Medical Services has resigned amid accusations that he allowed a mass casualty transport unit to be used to take guests to a wedding.

Bob Mixter resigned from his position with the county March 18, according to county spokesman Chip Boling.

Boling would not comment on what prompted the move. He did say that Mixter's resignation was unexpected and that he was not asked to leave.

Mixter's resignation came three days after he authorized using an EMS mass casualty transport unit to shuttle guests to and from a wedding March 15, Boling said.

Mixter could not be reached for comment.

Boling said he did not know who drove the unit during the wedding. The county did not pay additional gas fees as a result of the event, he said.

The unit was used March 17 to transport patients who were injured in Bonneau during a collision that involved a school bus, Boling said.

The transport unit headed to the scene within six minutes of receiving the call, he said. Boling added that the unit's response time was not affected by its prior use at the wedding.

According to Boling, the county's personnel manual prohibits the use of county property for personal use or business.

The county does not plan to pursue criminal charges or civil litigation against Mixter, he said.

EMS Deputy Director Becky Blair will serve as interim director until a nationwide search produces permanent replacement, Boling said.

Mixter held the position of EMS director since July 7, 2004, Boling said. No disciplinary action was taken against him during his time as director, he said.

Mixter was named the South Carolina Service Director of the Year in 2011.

Reach Christina Elmore at 937-5908 or at Twitter.com/celmorePC.