CHICAGO (AP and HOI) — Illinois prosecutors are suing the owner of a chemical plant where a fire last month sent dark smoke and ash into the air for days and prompted evacuations.

The lawsuit says the owner of the Chemtool plant near Rockton in northern Illinois should be held accountable for air and water pollution and hazards that still exist.

Illinois Attorney General Kwame Raoul and Winnebago County State’s Attorney J. Hanley filed the suit Friday in Winnebago County Court.

“The Chemtool fire rattled the community, displaced residents, and took the combined resources and efforts of several fire departments to get under control. Although the flames have been extinguished, the hazard posed to the public and the environment continues, and Chemtool owes the community more information,” Raoul said in a news release.

Raoul and Hanley’s lawsuit seeks to require Chemtool to assess the extent of the contamination, and take immediate corrective actions to address the release of pollutants to air, water and land. The lawsuit also seeks to compel Chemtool to take preventative actions to avoid the future release of pollutants, and pay civil penalties, the news release also said.

An estimated 1,000 residents were evacuated from the area around the plant after the June 14 fire, which authorities say was accidentally started.

Prosecutors say storage tanks holding about 100,000 gallons of petroleum product still being stored at the facility have been compromised and pose a “significant threat” to the area, including the nearby Rock River.