7 killed in U.S. massive car wreck

HOUSTON, Oct. 23 (Xinhua) -- At least seven people were killed and 25 others injuried in a massive car wreck on Monday due to a "superfog" of smoke from south Louisiana marsh fires and dense morning fog, authorities said.

State Police said on Monday night that 158 vehicles were involved in the ferocious crash and the death toll could be even higher.

Witnesses initially reported two deaths from a box truck that slid underneath an 18-wheeler, reported local media.

One tanker truck carrying a hazardous liquid was also reportedly off-loaded due to a compromised tank.

The superfog which led to extremely poor visibility was formed by smoke from local wetlands fires combined with dense fog. It is expected to be around for days.