WHITING, Ind. (AP) — BP has heard from more than 5,000 customers whose cars have required repairs associated with recalled regular gasoline in northwestern Indiana.

BP spokesman Scott Dead said Tuesday it's received 4,500 calls and 800 email messages since announcing the recall a day earlier.

The oil company says customers whose vehicles have experienced hard starting or other problems caused by the fuel should send it an email at bpconsum(at)bp.com or call 1-800-333-3991. Dean says customers should provide receipts for the repairs and fuel purchase, if available, or credit card bills showing the fuel purchase at affected retailers.

BP believes a 50,000-barrel batch of gasoline shipped from its Whiting fuel storage terminal Aug. 13-17 contained a higher level of a polymeric residue.

The company apologized for inconveniences caused to customers.