Mexican authorities arrested the widow of Temoac Mayor Valentin Lavin and the town’s police chief as part of an anti-extortion investigation.

Lavin was shot and killed during a town hall meeting on July 22 in the state of Morelos.

Prosecutors have not said whether the arrests are connected to the mayor’s murder.

Violence against local officials remains a major issue in Mexico, with dozens of mayors killed in recent years, CBS News has reported.

Authorities continue investigating both the extortion case and Lavin’s killing.