A damaged septic tank cover may be to blame for the death of a 3-year-old Montana boy who was reported missing last week but was later found dead not 10 feet from where he disappeared.

After two days of looking for missing Loic J.M. Rogers, searchers last Friday night found his body inside a 750-gallon septic tank at a family friend's home in north Evergreen, Mont. An autopsy found he had drowned.

Loic was reported missing Jan. 24 by his father, Mark Rogers, who said he put the toddler in his van, then went back inside the house to retrieve another sibling. When he came back a minute or so later, he said, Loic was gone.

Police have said there is no way a 3-year-old could have taken the 3-pound septic tank cover off himself.

The Daily Interlake in Montana on Wednesday reported that the septic tank's cover was damaged and not fitting properly.

Click here to read the Daily Interlake story

Flathead County Sheriff Mike Meehan told the paper and later FOX News that, during the last week of December, a vehicle at a nearby home had backed into the riser — a corrugated reinforced-fiberglass-plastic access tube that rises from the buried septic tank.

The impact cracked the exposed mounting, so the four screws used to attach the reinforced fiberglass plastic lid no longer fit, the newspaper reported. The driver promised to fix the damage but it wasn't done, Meehan said.

On the night Loic went missing, Meehan said searchers found the lid atop its riser.

"The lid was just sitting on there — it wasn't secure," he told FOX News on Wednesday.

But it's still "highly unlikely" Loic would have been able to enter the tank, then pull the lid over top of the hole, Meehan said.

"We are looking at all different types of scenarios" that could have happened, he said.

Searchers used a probe to search the tank, but found nothing. But two nights later, when the effluent was drained, Loic's body floated to the surface, apparently from the opposite end of the tank, Meehan told the Interlake.

An investigation is ongoing.

"At this point, we're not ruling out anything. We're still actively investigating it, ruling out people and until we do, we're not going to make any conclusions," Meehan said.

Loic's mother, Ariel Rogers, has confirmed she and her husband are in the middle of divorce proceedings and were battling for custody of their three children. Mark Rogers received temporary custody during the couple's separation.

"They are cooperating with us — both of the parents," Meehan told FOX News.

Asked whether police are investigating whether the dad could have been involved in Loic's death, Meehan said: "It's certainly something that we're looking at ... [but the custody battle] doesn't seem to have that much of a bearing on possible foul play."