CUTLER BAY, Fla. -

The owner of a Cutler Bay home where police say two children were injured when they were left alone and a fire started called the man renting the home a nice guy.

"I don't understand it," said Odney Johnson, who owns the one-story, single family home in Cutler Bay.

Johnson had been renting the home to Andrew Sepulveda, his girlfriend, their two children.

According to the arrest affidavit, Sepulveda, 31, left the two children -- a 6-year-old girl and 4-year-old boy -- alone at the home and locked the doors, which prevented them from exiting when a fire started in the children's bedroom Wednesday. Sepulveda went to pick up groceries with his girlfriend and their own children and left the other two children at the home.

"He was very courteous always and what I can't understand was he was very protective of his children and he really was just a nice guy," said Johnson.

Sepulveda was supposed to be babysitting the children injured in the fire while their mother was at work. The two families were living in the same house for nearly two months.

Johnson said he was unaware of the temporary situation.

"Four is what it was rented for -- four people," he said. "Two adults and two children."

Sepulveda is charged with two counts of child neglect with great bodily harm. He remained in jail Friday on $25,000 bond.

The two children remain at Jackson Memorial Hospital in serious condition.