Gardaí are investigating a suspected arson attack on the constituency office of Fine Gael TD Michelle Mulherin.

It happened at the premises in Ballina at around 7pm yesterday.

Gardaí had been called to investigate damage to a window when they saw the fire. It is understood the front window of the TD’s office was broken and flammable material was thrown into the premises.

Early reports suggest the incident was a petrol bomb attack — though gardaí would not confirm this, they said they are treating it as a case of criminal damage.

There was no one in the office at the time and it was quickly put out. The office sustained smoke damage which gardaí described as “minimal”.

In a statement last night, deputy Mulherin said she was thankful nobody was injured.

Deputy Mulherin has been under scrutiny after it emerged she had made calls from Leinster House to a private phone in Kenya.

The bill for the calls, which were made between 2011 and 2013, amounted to more than €2,000.

Ms Mulherin said she made the calls, but they were not personal in nature. However, she said she would repay the costs if Oireachtas authorities rule they were not all in line with her role as a TD.

The TD added the person she called was her friend and former campaign helper Danson Kole.

Ms Mulherin said the calls related to media reports about Mr Kole in 2012. However, Oireachtas phone records released under freedom of information legislation to RTÉ show that calls to that number had begun in the previous autumn.

She admitted the cost of the calls seemed high after it emerged that the Kenyan mobile number accounted for 38 of the 100 most expensive calls from Leinster House in 2011-2012.

Michelle Mulherin with Danson Kole

Ms Mulherin said: “None of (the calls) were personal. Indeed, for the most part, they pertained to a third party, who is a private citizen, who had been maligned and defamed in a newspaper article because of association with me and potential legal action arising there from.

“I had communications with Dan over a period of time and, as I say, he’s somebody that I would have dealings with in relation to political situations.

“I maintain the manner in which I used the phone was within the standard way, except it just happened to be somebody who was in Kenya."

Update: A man has been questioned and released. More

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