Nearly 100 letters and a petition were sent to Calderdale Council over Vodafone's plan for a mast in Granny Hall Lane, Brighouse.

Planning officials backed residents, believing it would dwarf the area and cause "visual clutter." They suggested an alternative site be found.

Residents believed their campaign in 2005 had been successful – only to find workmen preparing the site. Now council bosses are to apologise to all residents who objected, explaining why the mast has been allowed.

A spokeswoman said because the proposed mast was below 15 metres, it did not require planning permission.

"However, local authorities can request the siting and appearance of a mast to be considered if it responds within 56 days of being notified," she said.

"The council's request was not received by Vodafone within the time limit. Unfortunately, as a result of this administrative error, Vodafone have the necessary consent."

The council and Vodafone have failed to find an alternative site and the council said it was now investigating how the mistake happened.

Councillor Joyce Caw-thra said: "I have been told two letters were put in one envelope and that is why Vodafone never got a reply," said Coun Cawthra (Con, Brighouse).

"I will back any action residents' want to take. It needs a solicitor to see if this mistake should impact so much on residents."

Karen Johnson, whose Blackburn Road home overlooks the site, which is used for recreation, said: "It is incompetence and residents should have been kept informed on such a sensitive matter."

She wants further consideration given to an alternative site and suggested the cemetery 50 yards away.

She is demanding to know what action was being taken against the person responsible.

Keith Laycock, of Granny Hall Lane, said: "It's disgraceful when the people taxpayers pay for don't act on something."