Paris shooting: Fr Aiden Troy on extra security
A former Belfast-based priest, whose church is close to the Champs Elysee in Paris, had a sense there was "something in the air" ahead of Thursday's terror attack.
A policeman was shot dead and two others were injured by an Islamist gunman who was then killed by police.
Fr Aiden Troy was based in north Belfast during the 2001 Holy Cross school dispute, but now works in Paris.
He described a "grim scene" in the area after Thursday's attack.
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Fr Troy had been visiting parishioners and returned to the train station at the Champs Elysee about an hour after the attack, which was claimed by so-called Islamic State (IS).
"The Champs Elysee of course, rightly so, was closed completely to everything except to police and ambulances - there were still ambulances around when I arrived," said Fr Troy.
"There were some people who were trying to get back to their hotels and accommodation on the Champs Elysee itself.
"You could see there was quite a bit of distress and lots of small children because there had been a huge influx of tourists for Easter. So it was a pretty grim scene last night."
What happened on Thursday on the Champs-Elysees?
A car pulled up alongside a police bus just before 21:00 (19:00 GMT) and a man got out, opening fire on the bus with an automatic weapon, Interior Ministry spokesman Pierre-Henry Brandet said.
After killing an officer, the man attempted to run away while shooting at other officers, two of whom he injured, the spokesman added.
He was then shot dead by security forces.
Terrified eyewitness later recounted scenes of panic as they ran for cover after hearing gunfire.
The whole of the Champs-Elysees was evacuated.
Overnight, a property in the eastern Parisian suburb of Chelles was searched by investigators, who want to know who else - if anyone - may have known about the gunman's plans.
Fr Troy said security was very visible in the area before Thursday night's attack.
"I was going over to the school where I'm chaplain and I have never seen so many police, police checks - people being pulled in in motor cars," he said.
"I really got a sense there was something in the air."
The priests said that in the aftermath of the attack, as well as recent arrests in Marseilles and amid anxiety about Sunday's presidential poll, there was a real sense of concern in the city.
"I've been on the Champs Elysee this morning and like every other city, Belfast or wherever, traffic is running again, the street is open, I saw deliveries being made to restaurants, but there's still a sense of apprehension," he said.
"Maybe that's just me, but there certainly is something, people are really concerned now."
The gunman who carried out Thursday's attack has been identified from papers left in his car, but French officials are yet to release his name.
Local media say the 39-year-old lived in the city's suburbs, and had been seen as a potential Islamist radical.
So-called Islamic State (IS) said one of its "fighters" had carried out the attack.