Trade union head Tofiq Qorciyev said striking workers wanted the two managers who removed the posters thrown out of the country for insulting Azerbaijanis' feelings. Fighting over the region occurred from 1988-94, and an estimated 25,000 died.
A spokeswoman for McDermott, Gyulya Tagiyeva, said the company was investigating the incident.
It was unclear how many of the company's 3,000 Azerbaijani staff went on strike.
It was the second strike at McDermott in recent months. In November, workers set down their tools and demanded better pay.
The Nagorno-Karabakh Conflict
Click on the image to view an enlarged map of the Nagorno-Karabakh conflict zone
In February 1988, the local assembly in Stepanakert, the local capital of the Azerbaijani region of NAGORNO-KARABAKH, passed a resolution calling for unification of the predominantly ethnic-Armenian region with Armenia. There were reports of violence against local Azeris, followed by attacks against Armenians in the Azerbaijani city of Sumgait. In 1991-92, Azerbaijani forces launched an offensive against separatist forces in Nagorno-Karabakh, but the Armenians counterattacked and by 1993-94 had seized almost all of the region, as well as vast areas around it. About 600,000 Azeris were displaced and as many as 25,000 people were killed before a Russian-brokered cease-fire was imposed in May 1994.
CHRONOLOGY: For an annotated timeline of the fighting around Nagorno-Karabakh in 1988-94 and the long search for a permanent settlement to the conflict, click here.Click on the icon to view images of the Nagorno-Karabakh conflict (Flash required)
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