Mexican authorities acknowledge that a motorist tweeted them a warning about an impending mudslide on one of the nation's biggest highways hours before a massive slide swallowed two cars and killed seven people.

Twitter user Ricardo Miranda says his message could have saved lives. But the federal Transportation Department says the tweet referred to an unstable hillside about 3 miles (5 kilometers) from where the mudslide actually occurred.

The department says in a statement it saw Sunday's tweet and inspected the spot, but saw no danger.

Department spokeswoman Carolina Alvarez said Tuesday that several hours passed and an intense rainfall occurred between the time of the tweet and the mudslide.