The men aged 34 and 42 were arrested in the city this evening under section 41 of the Terrorism Act.
It brings to four the number of men arrested over the attack in Bishop Street outside the courthouse.
The other men – both aged in their 20s – were detained in Creggan this morning during early morning searches.
All four men remain in custody at present at the serious crime custody suite at Musgrave PSNI station in Belfast.
During the alert, residents and guests and staff at a local hotel had to be evacuated on Saturday night when police received information to clear the area around the courthouse.
A van hijacked from a pizza delivery driver in the city was left at the courthouse a bomb on board exploded.
There has been widespread condemnation over the attack from across the political divide.
PSNI Assistant Chief Constable Mark Hamilton said: “At around 7.55pm last night officers on patrol in Bishop Street spotted a suspicious vehicle and were making checks when, around 5 minutes later, information was received that a device had been left at the courthouse.
“We moved immediately to begin evacuating people from nearby buildings including hundreds of hotel guests, 150 people from the Masonic Hall and a large number of children from a church youth club. The device detonated at 8.10pm.
“At this stage it appears as though the vehicle used had been hijacked from a delivery driver in the Quarry Street a short time before the explosion.
“This attack was unbelievably reckless.
“Thankfully the attackers failed to kill or injure any members the local community out socialising and enjoying the best of what the city has to offer.
“The people responsible for this attack have shown no regard for the community or local businesses.
“They care little about the damage to the area and the disruption they have caused.
“The area remains sealed off and church services at St Augustine’s has been moved to St Peters and the Cathedral services have been cancelled this morning as a result.“We are incredibly grateful for the support and co-operation of the local community.
“I am appealing to anyone with information to please get in touch with us on 101. Information can also be given to Crimestoppers anonymously on 0800 555 111.”
The Mayor of Derry City and Strabane District Council, Councillor John Boyle condemned Saturday night’s attack.
Speaking close to the harrowing scene, Mayor Boyle said that he was at a loss for words following a ‘blast bomb’ explosion outside Derry’s courthouse.
“For the people who have done this tonight, they have disrupted and threatened lives this evening,” Mayor Boyle said.
“These actions belong in the past and it should have stayed in the past and, really I would ask a simple question, what was this all about?”
Mayor Boyle continued: “What do you think you have achieved here tonight by doing this? When you brought this van into the city centre, hijacked it from a hard-working member of this community and exploded a device?
“What has this achieved?”
Mayor Boyle insisted, despite the nature of the act, the people of Derry do not want a return to the city’s troubled history.
“All right-thinking individuals in this city will appreciate and recognise this is a vestige of our past.
“We have all moved beyond this some considerable time ago,” he added.
“Therefore, we are also looking at a situation where people are saying you are not doing it in our name.
“So, if you are not doing it in anybody’s name, why are you doing it?”
“This is an attack on the local community,” Boyle stressed.
“There are people who are very determined to move this place forward.
“The question I would ask them is, are they determined to move this place backwards? That is what it looks like.”
Tags: