CHACKBAY — Port Allen police officer Robert Cannon doesn't consider himself a hero, but it's what he says he police chief is starting to call him after his involvement Wednesday in the rescue of a man who got trapped inside his SUV when he ran off the road and crashed into a nearby waterway. 

Wednesday's crash, which occurred around 6 p.m. along La. 20 in Lafourche Parish, was the second time within a two-week period the 18-year law enforcement veteran got involved in the rescue efforts of a traffic accident while he was off duty. The first was on July 21 when him and another man helped pull an elderly woman from a truck that had overturned on the new Mississippi River Bridge in Baton Rouge while he was driving into Port Allen for work. 

Two people pulled a Houma driver out of Bayou Chevreuil in far northern Lafourche Parish Wednesday evening after the driver's SUV went off La. 20 and into the waterway, authorities said.

St. James Parish Sheriff Willy Martin Jr. said a law enforcement official from Port Allen driving a few vehicles behind the SUV and another person rushed to pull the driver from the water once it went into the bayou.

Though the rescuers could not find out from the driver whether anyone else was in the SUV, authorities later determined no one else was inside the submerged vehicle, Martin said.

The SUV went into the bayou between South Vacherie in St. James Parish and Chackbay in Lafourche Parish shortly before 6 p.m.

Martin said the crash happened just south of the St. James line about half-mile south of the Bayou Chevreuil boat launch. The bayou or its tributaries run along La. 20 in the area of the crash.

The crash caused heavy traffic backups on La. 20 as rescue crews tried to get to the scene.

The driver's and rescuers' identities were not immediately known Wednesday evening.

Follow David J. Mitchell on Twitter, @NewsieDave.