Pretoria - First National Bank has apologised for an offensive tweet sent on Tuesday from the bank's "FNB Guy" account about a bomb being placed under a paralyzed person's wheelchair in Afghanistan.

"FNB is disappointed in & sincerely apologises for the tweet re Steve. The comment conflicts with our corporate values and has been retracted," a tweet read from the same account.

Earlier on Tuesday a man by the name Stu posted the following tweet:

"@fnb where has Steve disappeared to? Your radio campaign just isn't the same,” posted by Stu (@gormleystuart).

In response, the FNBGuy account under the name @Rbjacobs responded by saying:

"He's some where (sic) in Afghanistan, putting a bomb under a wheelchair and telling the cripple to run for it!"

FNB CEO Jacques Cilliers then tweeted: "Apologies for the @Rbjacobs wobble .. experts are investigating quickly."

The bank could not be reached for comment.