From Longman Dictionary of Contemporary Englishalarm bells ringalarm bells ringif alarm bells ring, you feel worried that something bad may be happening Alarm bells started to ring when he failed to return home. → alarm
Examples from the Corpus
alarm bells ring• Nor had any alarm bells rung about Thomas.• But alarm bells rang when Allison wrote back in December.• At Police Headquarters alarm bells rang in from government munition dumps, military vehicle compounds, hi-tech weapon factories and sweet shops.• Her flesh cried out to be closer, and, with the last vestiges of sanity, alarm bells rang.• More precisely, one complaint from a parent actually appeared, but this was enough to set alarm bells ringing.• Between them, in their flight from the mill, they'd set all the alarm bells ringing at the local sub-station.• Maybe when they didn't phone home, the alarm bells rang.