Walsall Council is investigating its communications department after its official Twitter account was used to make fun of a senior government minister.
The council's Twitter account was used on Saturday evening to share a link to a picture of ventriloquist Ray Alan's dummy Lord Charles, who was often portrayed as drunk, claiming it looked like education secretary Michael Gove. It ended with #saveusfromtheposhboys, which was added by whoever had accessed the council account.
Using a "#" before a word means Twitter users can click on it to see other mess-ages about the same subject. The message was deleted after Twitter users complained. The council claimed its account had been hacked.
But its Conservative leader has now said it was a "human error" and that the official will be "chastised".
The council wrote: "It appears our account has been hacked. We apologise for any offence from earlier tweets / use of hashtags.
"To reiterate our earlier statement, we once again apologise for an unauthorised tweet sent via our account at around 7pm this evening. This matter is now the subject of an internal investigation."
The Conservative MP Louise Mensch, a member of the House of Commons culture, media and sport committee, accused the council of trying to cover its tracks. She wrote: "Who wakes up in the morning and thinks 'I know, I'll hack Walsall Council's Twitter account?' Tell the truth, who posted that?"
An investigation has now been launched by councillors. The council's officers must be politically neutral.
Council leader Mike Bird said it was believed the tweet had been sent by someone in the authority's communication team who thought they were using their own personal account.