LUCKNOW, Dec. 24 -- Dense fog caused a massive multi-vehicle pile-up on a national highway in Amethi district early Tuesday, killing two people and injuring 18 others, senior police officials said.

Amethi additional superintendent of police (ASP) Gyanendra Kumar Singh said the accident occurred around 2 am near the Amethi-Sultanpur turn, close to an under-bridge in the Musafirkhana police station area limits, when visibility dropped sharply due to thick fog.

He said a truck crashing into a roadside railing triggered a chain of collisions as vehicles following close behind failed to stop in time. At least seven vehicles, including a Uttar Pradesh Roadways bus, three trucks, a car and another heavy vehicle were involved in the crash.

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