About 200 people staged an early morning protest yesterday on the second day of work at the Shell Corrib gas terminal in north Mayo.
A force of 170 gardaí escorted Shell staff and contractors on to the site early yesterday.
"We will remain here as long as is necessary to keep the peace and ensure that people can get to their places of work unhindered as well as to ensure the safety of protesters," Insp Ray McHugh of the Garda Press Office said. The situation would be reviewed at the weekend, he added.
Site workers arrived in a convoy of four-wheel drives, vans and lorries before 8am yesterday. The convoy received a hostile reception from the protesters at the Bangor Road junction, three-quarters of a mile from the terminal site at Bellanaboy.
In a highly-charged atmosphere, Willie Corduff, a landowner on the pipeline route and one of the five men imprisoned last year for his opposition to it, complained about being "pushed and hemmed in" by the gardaí and appealed to them to stop the practice.
PJ Moran, a prominent Shell to Sea campaigner, complained to gardaí that roads had been closed for the benefit of Shell. "I had to travel 10 miles to get here even though I am living only three minutes over the road from the site."
Shell to Sea spokesman Dr Mark Garavan expressed doubt yesterday that using "hundreds of gardaí" was a sustainable way of bringing the Corrib gas project forward.
The human rights organisation Frontline has sent observers to monitor the continued stand-off. The organisation said that its staff visited the terminal site yesterday with two international lawyers specialising in human rights.
Andrew Anderson, deputy director of Frontline, said its focus was ensuring that there was a respect for human rights and freedom of communities to engage in a legal protest.
The non-governmental organisation Afri has called on the Government to insist that Shell should "desist" immediately from its activities and agree to process the gas offshore.
The Government should not "emulate the role of the Nigerian government during the crisis there in the 1990s, when that government colluded in the executive execution of Ken Saro-Wiwa and eight members of the Ogoni community", Joe Murray of Afri said in a statement.
Meanwhile, the Fianna Fáil party in Mayo has deplored "the negative attitudes of some parties" in the dispute which, it says, is "preventing much needed gas from coming ashore".
The statement continued: "Individuals or parties involved in prohibiting a successful resolution to the problems in Bellanaboy should immediately withdraw as the only purpose they serve is to further damage the north Mayo region as an attractive location for development both now and in the future."