Chem Alarm at Minn.-St. Paul Airport Sends 19 to Hospitals

Pepper spray or Mace was likely to blame for closing the area around a checkpoint

Hogan said that the cause of that incident was never determined but that authorities do not believe it was a threat to airport safety.

There is no indication Tuesday's incident was linked to President Bush's visit to the Twin Cities that afternoon, and it did not affect his trip, Hogan said.

Hogan did not expect any problems with air travel today.

Staff writer Joy Powell and the Associated Press contributed to this report. Chao Xiong - 612-673-4391