Jewel-Osco parent Supervalu’s stock shot up 45 percent Monday on fresh reports that a private equity group is working to buy out the embattled supermarket chain.

Reuters reported that Cerberus Capital Management is working on a takeover bid for Minnesota-based Supervalu Inc., citing unnamed sources. Earlier, the Debtwire news service reported that Cerebrus was trying to arrange $4 billion to $5 billion in debt financing to back a bid.

Supervalu’s stock closed at $3.17 Monday, up 98 cents. The company declined to comment on the Cerberus buyout speculation.