A man remains in a serious condition in hospital after his tent on the banks of the Grand Canal in Dublin was removed by an industrial vehicle on Tuesday afternoon as he slept.

A number of investigations are under way into the incident, which happened at the junction of Wilton Terrace and Leeson Street during clean-up works being carried out by Dublin City Council and Waterways Ireland.

The unnamed man, who is from Eritrea and is thought to be in his 30s, has undergone surgery at St Vincent's University Hospital for injuries that have been described as "life-changing".

The incident is being investigated by gardaí and the Health and Safety Authority, while Waterways Ireland and the Dublin Region Homeless Executive have undertaken separate reviews.

Homelessness charities are calling for an independent investigation.

Gardaí have appealed to anyone who may have witnessed the incident or any road users who may have camera footage to contact Gardaí at Pearse Street on 01 666 9000, the Garda Confidential Line on 1800 666 111 or any Garda station.

Homeless campaigner Fr Peter McVerry said the Health Information and Quality Authority should be given the responsibility to go into hostels, which accommodate homeless people to carry out checks on them. 

Speaking on RTÉ's Morning Ireland, he said if that were to happen, many of them would be "closed down overnight".

He said some homeless people are choosing to stay in tents over hostels, with safety being one of the main reasons. . 

"Some are excellent but many don't feel safe in those hostels."

He said one of the biggest complaints he gets from homeless people who choose to stay in hostels is being assaulted

He said people are often sharing a room with five or six other people that they do not know and "they could be injecting heroin or have a serious personality problem."

He said in one recent incident a man in a shared hostel room started stabbing his mattress with a knife during the night. 

He said it is harder to get homeless people out of tents and into roofed accommodation and many are frightened to go into hostel accommodation. 

Fr McVerry said he finds it particularly frustrating when people who do not use drugs have to share hostel rooms with drug users.

The Dublin Region Homeless Executive said it would be confident that it's hostel accommodation would meet HIQA standards.

In a statement the DHRE said emergency accommodation is subject to unannounced inspections by council environmental officers and there is a complaints procedure.

It said it had also opened 340 extra private rooms for single people and couples over the past year.