A Southwest Airlines flight from Chicago to Sacramento made an emergency landing Monday morning after a passenger tried to jump out through a rear emergency exit door.

Witnesses said they heard a flight attendant screaming "Help me, help me!" from the rear of the plane. Passengers reacted quickly, running to the back and tackling a man who was trying to open an emergency door.

One passenger said the man was acting strangely earlier in the flight, too, getting up to go to the bathroom and coming back "soaking wet."

The plane landed safely at Omaha's Eppley Airport, where the "unruly" passenger was escorted off, a Southwest spokesperson said. Flight 722 finally arrived in Sacramento about 2 hours late.

The FBI is investigating the incident.

[Photo: NBC Chicago]