By Dave Kaup

ATCHISON, Kansas (Reuters) – City and county officials told residents of Atchison in northeastern Kansas it was safe to return after a chemical spill at an MGP Ingredients Inc facility on Friday caused the formation of a chemical cloud that forced evacuations.

Thirty-four people were being treated for respiratory discomfort, although the injuries appeared to be minor, Trey Cocking, Atchison city manager, told reporters. The city said in a statement on social media that the chemical cloud had lifted.

“We are in the process of issuing an all-clear,” Cocking said. “Students were evacuated from their schools this morning. They are being allowed to return at this time.”

Cocking did not identify the chemicals involved in the incident in the city of about 11,000 people located about 50 miles (80 km) northwest of Kansas City, Kansas.

First responders are seen at the scene of a chemical spill at a facility in Atchison, Kansas, U.S., October 21, 2016. Courtesy Emma Matlock/Handout via REUTERS

A Fox station in Kansas City reported that an emergency management team’s spokesperson said the chemicals may have been sulfuric acid and chlorine.

Founded in 1941, MPG Ingredients employs 320 people, according to the company website. It makes bourbon and rye whiskeys, gins and vodkas, according to the website.

The incident occurred when two chemicals were mistakenly mixed at the MGP Ingredients facility, Cocking said.

Cocking said MGP employees were being allowed to return but it was unclear if the facility would re-open on Friday.

(Reporting by Timothy Mclaughlin in Chicago and Ben Klayman in Detroit; Editing by Bill Trott and Will Dunham)