Three explosions rocked the departures area of the international terminal of Istanbul’s Ataturk airport Tuesday night, resulting in 36 deaths and more than 140 injuries. The death toll is expected to rise.

Turkish police reportedly exchanged gunfire with three attackers armed with Kalashnikovs in an effort to neutralize them. During the gunfight, the attackers blew themselves up, according to a Turkish official.

It was originally reported that there were only two explosions and two attackers; that number was revised to three.

Several reports noted that Ataturk has stringent security protocols: passengers must go through security multiple times. The exchange of gunfire occurred outside the initial security permitter that surrounds the airport entrance. It occurred around 10 p.m. local time.

Ataturk is the largest airport in Turkey, the third largest in Europe, and a major hub for Turkish Airlines. According to statistics compiled by Airports Council International, Ataturk was the 11th busiest airport worldwide in terms of the total number of passengers in 2015.

The U.S. Department of State had just issued on Monday a travel warning to Americans traveling to Turkey. Among the safety precautions prescribed, the warning advised Americans to “avoid travel to southeastern Turkey, particularly near the Syrian border” and to “stay away from large crowds, including at popular tourist destinations.”

Atatürk Havalimanı dış hatlar terminalinde önce silah ve çatışma sesi, sonra 2 patlama sesi duyulduğu belirtildi. pic.twitter.com/1u2FVjUb4Y — 140journos (@140journos) June 28, 2016

This photo shows impact of explosions at entrance of int’l terminal Atatürk airport in Istanbul. #Turkey pic.twitter.com/KuNUfv2Qye — Yannis Koutsomitis (@YanniKouts) June 28, 2016

MORE: Two explosions hit Istanbul’s Ataturk airport, multiple injuries: Turkish official — Reuters UK (@ReutersUK) June 28, 2016

1st photo from Istanbul’s Ataturk airport where 2 major blasts rocked int’l terminal, leaving multiple casualties.pic.twitter.com/xhu1uMfzTS — Mustafa Edib Yılmaz (@MustafaEdib) June 28, 2016

Videos appeared on Twitter and Instagram, apparently of passengers taking shelter in the airport:

Взрывают и стреляют , не знаю как улететь ??Terrorist attack in Ataturk airport #Istanbul A video posted by Yana (@yana_chizhanova) on Jun 28, 2016 at 12:02pm PDT

An itibari ile Atatürk Havalimanı pic.twitter.com/K6zkTKJfGa — MANYAK (@manyakkkkkkkkk_) June 28, 2016

UPDATED — 29 June 2016 7:28 a.m. ET: NBC News is reporting that the numbers of deceased and injured have both risen since last night:

Terror in Istanbul update: 41 dead, 239 injured in Turkey attack pic.twitter.com/hcD63uADhc — Morning Joe (@Morning_Joe) June 29, 2016

UPDATED — 29 June 2016 9:24 a.m. ET: One of the attackers was caught on video just as he detonated his suicide bomb.

Wow the police actually shoots one of the suicide bombers before he blows himself up. #Istanbul pic.twitter.com/7kJzWJycyP — Gilgo (@agirecudi) June 28, 2016

This story has been, and will continue to be, updated.

[file photo above via Wikicommons]

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