Courtesy Art A graphic provided by the FBI Detroit Field Office appears.

ALPENA — Sextortion schemes targeting Michigan children are on the rise, the FBI’s Detroit field office warned parents on Wednesday.

In the schemes, adults posing as young girls coerce boys, usually between 13 and 17, to engage in explicit activity over video and then threaten to post video of that activity online if the victim refuses to give them money, the FBI said.

The agency recommends that parents avoid posting personal information online, block messages from strangers, be suspicious of people they and their children meet online, and encourage children to report suspicious behavior to a trusted adult.

Residents with tips about possible sextortion scams can call 313-965-2323 or visit tips.fbi.gov. Do not delete suspicious material before law enforcement reviews it, the FBI recommends.