MIAMI (AP) _ An apparent attempt to cover up a drug trafficking probe involving a former Metro-Dade police officer is suspected of setting off Everglades brushfires that shrouded Miami in smoke last week, officials said.

Charred documents found by firefighters at the source of the 12,000-acre blaze that started April 8 have been linked to Alex Marrero, 34, according to Joe Subic, an investigator with the Florida Department of Agriculture.

Nine years ago, the acquittal of Marrero and three other Metro-Dade officers charged with beating a black man to death in Miami launched three days of riots that left 18 dead and an estimated $80 million of property damage in Miami's black neighborhoods.

The documents, soaked in gasoline, belonged to Eastern Security and Investigations Inc., a Miami-based company owned and operated by Marrero. Police suspect the documents were burned in connection with Marrero's arrest in a sting operation earlier the same day.

The fire broke out only hours after Marrero's arrest, along with Drug Enforcement Administration agent Jorge Villar, on cocaine distribution and bribery charges. They could face up to life in prison if convicted.

Subic acknowledged that Marrero's arrest made it impossible for the former Metro-Dade police officer to have started the fire. But the investigator speculated that Marrero could have passed an order to an associate to burn the company records.

According to Subic, arson charges will be brought against whoever started the fire.

State and federal firefighters worked for more than three days to control the blaze, which shrouded Miami and much of South Florida in a dense cloud of smoke. It caused $100,000 in damage, Subic said.