Reunion Mission: Faith in the Face of Crime (Rangers Under Fire Book 2)

FRAMED 

Lured into a dark classroom, high school teacher Claire Kendall stumbles over the body of a dead student—and into the clutches of the killer. Certain she's about to die, Claire is shocked when DEA agent Matt Ross bursts in and rescues her. The former army ranger who broke her heart ten years ago is back in town to bust a drug trafficking ring operating at the school. With Claire being framed for the young informant's murder, she has to put aside their past and trust her handsome ex to keep her safe. But someone is dead set on bringing their hometown reunion to a permanent end. 

Rangers Under Fire: Nothing's more dangerous than falling in love.