Sinn Fein (search) party leader Gerry Adams went to the United States on Saturday in search of foreign support, but back home in Northern Ireland (search) a controversy over the IRA's killing of a Catholic man refused to go away.

Sinn Fein, reeling from accusations its members helped destroy evidence and intimidate witnesses, admitted a party election candidate was present in the bar where Irish Republican Army (search) members attacked Robert McCartney.

Adams left Northern Ireland before the latest development. During his weeklong trip to the United States, he said he would emphasize that "the peace process has to be put together again" and would laud Irish-American backers who have "remained with this process through thick and through thin."

"The process is in crisis," Adams told supporters at a reception at a Cincinnati hotel after arriving in the United States. "We in Sinn Fein are totally determined to keep pushing the process forward. I think we will see a way out of these difficulties; I just don't see any option, no option at all."

Sinn Fein initially objected to police efforts to identify McCartney's killers, while the outlawed IRA denied any involvement. Both wings of the Irish republican movement have had to change their position drastically because of a campaign by McCartney's five sisters, who will be guests of the White House on St. Patrick's Day (search).

In response to the sisters' highlighting of witness intimidation and IRA involvement, the underground group has expelled three members, while Sinn Fein has suspended seven of its own. Adams also has told witnesses to offer statements to a police-complaints official, but not directly to the detectives investigating the killing.

Adams said Saturday night he was embarrassed and disappointed by the apparent involvement of Sinn Fein and noted it has suspended seven party members.

"Those do not reflect the decent hundreds of thousands of republicans who are damned by the one or two or three or four or five or six or eight or nine or whatever amount of people were involved in that dreadful killing," Adams said.

Adams will be in New York and New Jersey on Monday, then Philadelphia, Washington and Cleveland. He has not been invited to the White House or any official government function, although he plans to meet with Massachusetts Sen. Ted Kennedy and others on St. Patrick's Day.

"I think that the president has not invited any of the (Irish) political parties is a disappointment," Adams said.

The IRA caused widespread outrage when it revealed Tuesday it was willing to kill four people allegedly involved in the attack.

Now, in the latest twist in this unprecedented confrontation between Sinn Fein and its own working-class Catholic grass roots, a young Sinn Fein candidate in Northern Ireland's most recent elections confirmed she had been inside the pub where McCartney was attacked.

Cora Groogan, 23 — who ran unsuccessfully in the 2003 elections for Northern Ireland's legislature alongside Sinn Fein deputy leader Martin McGuinness — said she had provided a statement to her own lawyer about what she had seen but would not talk to police about it.

"I got to the bar about 10 p.m. that Sunday. I was there for a short while," she said. "There was a commotion in the bar but I witnessed nothing and left shortly after 11 p.m."

Police and witnesses say McCartney and his friend Brendan Devine were attacked between 10 p.m. and 11 p.m. inside the bar, allegedly after a senior IRA figure was offended by something one of them had said and threatened, "Do you know who I am?"

Witnesses, speaking to journalists and the McCartney family, have described seeing the IRA figure order henchmen to slash Devine across the neck with a broken bottle, then pursue both McCartney and Devine outside, where the 33-year-old McCartney was clubbed with iron rods and had his throat and stomach cut open with a knife.

He died hours later — after IRA figures allegedly ordered approximately 70 people inside the bar not to talk to police, nor to phone for an ambulance.