Northern Ireland leaders and Barack Obama discuss Adrian Ismay death
Northern Ireland's first and deputy first ministers have discussed the death of a prison officer in Belfast during a meeting with the US president.
Arlene Foster and Martin McGuinness were in Washington DC as part of a trip aiming to secure US investment deals.
The White House meeting with Barack Obama came after Adrian Ismay, who was recently injured in a bombing, died.
Mr McGuinness said he told the president Northern Ireland would "stand together" against Mr Ismay's attackers.
Mr Ismay died on Tuesday, 11 days after a booby-trap bomb exploded under his van.
Dissident republicans said they were behind the attack.
"We know the strategy of these people who are committed to try to plunge us back to the past is to destroy everything that we've built up collectively over the past 20 years," Mr McGuinness said.
"We're not going to let that happen.
"We emphasised to the president and to all those in authority here in the United States that we're going to stand together."
During a lunch attended by the ministers, Mr Obama referenced the Northern Ireland peace process as a potential example for the world.
Mr McGuinness said "the powers that be" in the US saw the peace process "as a beacon of hope".
"They acknowledge that many other areas could learn from the experiences that we've been through."
He added that Mr Obama had been "full of praise" for how Northern Ireland's politicians struck the Fresh Start agreement in November that lifted Stormont from a three-month crisis.
Mrs Foster said she was determined that the purpose of the visit would not be derailed by talk of violence in Northern Ireland.
She said the focus during the meeting with Mr Obama had been on "the fact we were creating hope in Northern Ireland".
"Obviously we were shocked and saddened by the news from home," Mrs Foster added.
"But we cannot allow our trip here to be diverted in relation to the message that we have in terms of Northern Ireland moving on."