There are several important issues.
State media of Belarus released a recording of the shootout. During the shootout, IT manager Andrei Zeltser and a KGB officer who tried to conduct a search in Andrei's apartment were killed. According to the law enforcement bodies, Zeltser used a hunting shotgun to shoot the members of the investigation team who came to his apartment.
The authoritative BBC has had some questions about the recording and asked experts to comment on it.
A video published by the pro-government media shows men in plain clothes demanding the owners to open the door of an apartment. After that, they open it with an angle grinder and break in.
Other footage made inside shows a man with a hunting shotgun. A shootout starts; one of the intruders falls down and blood spreads over the floor.
It is not known who made the footage
Where's the footage from Zeltser's wife's phone?
The 26th second of the video shows Andrei Zeltser with a hunting shotgun. The camera is behind Andrei's back. It was fixed, as the picture is clear as it cannot be done when the camera is in hands.
One can see a woman in the room who also takes the video on the phone (28th second; one can see her reflection on the TV screen). The Belarusian media say it's Zeltser's wife.
However, it's not clear why the video from the girl's phone was not published. The girl is detained, as the law enforcement agencies report, she is suspected of complicity in the murder of the KGB officer.
The fragment of the video with gunshots shows only the hands of the shooter, but not his face or torso. The former head of the third department of the Belarusian Serious Organised Crime and Corruption Agency (GUBOPiK), Alexander Azarov, who is now a member of the opposition association of former law enforcers of Belarus Bypol, points this out.
"They took away [the wife's] phone with the video. But they could have shown footage from her phone showing Andrei shooting. People wouldn't have had questions then," Azarov told the BBC. "Instead they pasted in a strange piece where one can't see who is holding the shotgun. There's something they don't want to show," he suggests.
Curtains and open window
Footage taken inside the apartment, up to the 36th second, shows the windows tightly curtained with striped curtains. This is also reflected on the TV screen.
However, the 55th second of the video shows the curtains are already open. The reflection on the TV shows a girl in black pulling the window handle; the frame slowly opens. It happens against the background of gunshots.
The uniforms of the security forces
Footage taken on the stairwell shows a group of men trying to enter the apartment, then bursting the door in. The enforcers wear plain clothes: jackets and caps.
At the same time, an official statement from the KGB says the officers were on a special operation "to investigate addresses where persons involved in terrorist activities might be located" and there was "a dangerous special criminal" in the apartment, according to the agency.
In such a case, it is unclear why the law enforcers did not wear protective equipment such as helmets, body armour or shields, Azarov said. "If they were working on terrorists, the officers should have been wearing armoured jackets, special clothes with the name of the unit, helmets, shields and machine guns," says a former GUBOPiK officer. - Since they wear plain clothes and have no protection, they assume there is no terrorist but an ordinary IT worker".
On Belsat TV, another Bypol spokesman, former prosecutor Oleg Talerchik, also drew attention to the lack of equipment.
"If they considered Andrei Zeltser a dangerous special criminal and were going to detain him as a dangerous special criminal, they were obliged by all instructions - ask any police officer - to use the permit system to check whether he had a registered weapon," said Talerchik. - And he had one, and it was registered because he was a hunter."
"[It was] necessary to check the area, find out the plan of the apartment and enter it fully equipped: not to spend half an hour breaking down the door with unclear devices, but through windows, as they do," continued Talerchik.
The video shows Zeltser holding a double-barreled hunting shotgun with vertical barrels. This August 13th, Zeltser posted a picture of a similar shotgun on one of his Instagram accounts. On the same day, the website iHunt.by published information about the payment of hunting fees in the name of Andrei Zeltser.
A weapons expert, interviewed by the Russian BBC Service, assumed it was a sport-hunting shotgun IZh-27. Some media also reported it. Smoke is often produced when one shoots with such shotguns. But there was no smoke on the video.
However, the expert says certain conditions of shooting (including brightness) can make no smoke visible. The cartridge filling and other variables may also influence the presence or absence of smoke.