Ian Walsh (49) was discovered dead in his home.Táilte Tours/Facebook

Ian Walsh, 49, was discovered in a pool of his own blood at his home in Carrick-on-Suir, Co. Tipperary, at the start of this month. Gardaí [Irish police] confirmed they arrested a teenager yesterday.

The arrest comes after gardaí trawled through Mr Walsh’s social media profiles, as well as call and text logs. It is understood that gardaí are investigating whether Mr Walsh had befriended the man online and had invited him to his home.

Security sources said there were no visible signs of forced entry to Mr Walsh’s home, and it appeared he let his killer into his home. Another avenue of investigation is that Mr Walsh was attacked after foiling a robbery at his home. However, this has since been discounted since there was no evidence of a forced entry.

"Forensics are looking through his digital footprint, his phone, social media profiles, and are looking to see if they can find anyone who was with him at the time of his death," said the source.

"By all accounts, Mr Walsh was a gentleman and was not an aggressive man in any way, shape, or form."

A Garda spokesman said they had "arrested an adult male, aged in his late teens, in relation to this investigation" yesterday, adding:

"The male is currently detained under Section 4 of the Criminal Justice Act 1984 at a Garda station in the Clare-Tipperary Division."

 Mr Walsh – who was known to friends as Squinty – worked for Irish Rail for decades. He was also involved in organizing rail tours around Ireland.

At the time of his death, Táilte Tours, which had worked with Mr Walsh for years, said his nature made him friends with anyone he met.

 A spokesman praised their "signaler at Cork station" and "huge supporter" of their tour operation, who "went far beyond the extra mile to ensure our operations went off without a hitch". Iarnród Éireann also paid tribute to him.

* This article was originally published on Extra.ie.