Shoppers were evacuated from the Asda supermarket on Kingswood because of a bomb threat.
Staff received a call at 10.30pm last night warning there may be a bomb in the store.
The callcame in four minutes after a similar call was made to an Asda store in Grimsby.
An Asda spokeswoman said the supermarket was evacuated and police called.
A police investigation revealed the call to be a hoax and the store was re-opened at 11.15pm.
A spokeswoman for Humberside Police, said: "Humberside Police are investigating after a hoax call was made to Asda in Grimsby, and to Asda in Hull.
"At 10.24pm a call was made to police in Grimsby reporting that a unknown person had called the Asda store, in Holles Street reporting that an explosive device had been placed in a specific location in the store. A search of the store was conducted and no device was located. The store was not evacuated.
"At 10.28pm a similar call was made to Asda in Bude Road, Hull, reporting that an explosive device had been placed inside the store, however its location was not known. The store was evacuated and after a search nothing was found.
"Police have reason to believe that both incidents may be connected and enquiries are ongoing."
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