诈骗 = to defraud / swindle;
犯 = criminal / offender. The
犯 suffix builds many crime-actor terms in Chinese:
杀人犯 (murderer),
强奸犯 (rapist),
抢劫犯 (robber),
走私犯 (smuggler).
电信诈骗犯 (telecom fraudster) is the most common modern collocation thanks to widespread phone-scam crackdowns in China.