The pilot of a hot air balloon involved in a fatal Texas crash had spent time in jail for drink-driving and drug convictions. Alfred "Skip" Nichols was one of 16 people who died on 31 July after the balloon caught on fire and crashed into a pasture near Lockhart, a city located south of Austin.

Nichols was convicted of drink driving at least four times in Missouri and he spent time in prison twice, court records show. He pleaded guilty to driving while intoxicated in 1990, twice in 2000 and on another occasion in 2010.

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After being found guilty of a drug-related crime in 2000, Nichols spent about 18 months in prison before he was released on parole.

The pilot's ex-girlfriend, Wendy Bartch, said he had been sober for at least four years and claimed he put his passengers' lives first. "He did not fly when he wasn't supposed to. Having other people's lives at stake was Skip's primary concern," said Bartch.

Authorities are yet to publicly name the victims. However Nichols' roommate, Alan Lirette, identified the 49-year-old as the pilot and paid tribute to him.

"That's the only thing I want to talk about, is that he's a great pilot," Lirette told The Associated Press (AP) from a property that he shared with Nichols in Kyle, Texas. "There's going to be all kinds of reports out in the press and I want a positive image there too."

Investigators believe the hot air balloon collided with high tension power lines before crashing down to the ground. Local resident Margaret Wylie initially thought a vehicle was on fire and described what looked like "a fireball going up."

In 2008, the Better Business Bureau (BBB) issued a warning to consumers about the risks of doing business with Nichols following a number of complaints against his balloon company.