[handwritten]: Gorbachev

Secret

Copy Nº [left blank]

[two illegible addressees handwritten across

the top left-hand part of the page]

[to the] CPSU CC

[Letterhead of the USSR First Deputy

Minister of Power and Electrification]

26 April 1986   Nº 1789-2s

[faded CPSU CC

General Department stamp]

Concerning the accident at unit Nº 4

of the Chernobyl AEhS [Atomic Power Station]

URGENT REPORT

At 0121 26 April 1986 while taking power unit Nº 4 of the Chernobyl AEhS out of operation for scheduled repair an explosion occurred in the upper part of the reactor chamber after the reactor shut down.

According to reports from the director of the Chernobyl AEhS the roof and parts of the wall panels of the reactor compartment, several roof panels of the machine room and of the auxiliary systems unit of the reactor compartment were demolished during the explosion and the roofing caught on fire.

The fire was extinguished at 0330.

The personnel of the AEhS are taking steps to cool the fuel core of the reactor.

In the opinion of the 3^rd Main Directorate of the USSR Ministry of Health it is not required to take special measures, including the evacuation of the population from the city.

Nine of the operations personnel and 25 of the militarized firefighters have been hospitalized.

Steps are being taken to eliminate the consequences and investigate what happened.

[signature]

A. N. Makukhin

[handwritten at the bottom:]

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