(LAFAYETTE, Louisiana) -- Missing Louisiana student Michaela "Mickey" Shunick's recovered bike suffered significant damage to the rear tire, including a bent rim, authorities said on Wednesday.
The bike was discovered in a muddy basin under a bridge Sunday morning, but authorities had been tight-lipped about its condition. The bike was about 27 miles from where Shunick, 22, was last seen on surveillance footage riding her bike home from a friend's house at around 2 a.m. on May 19 in Lafayette, La.
"We strongly believe that the person, or perpetrator, drove down to the edge of the water and dumped the bike into the water for it not to be found," Cpl. Paul Mouton of the Lafayette Police Department said.
The fact that the bike was found damaged and dumped near a highway suggests Shunick might have been hit by a car, ABC News consultant and former FBI special agent Brad Garrett said.
"If her bike was hit by a vehicle...you may be able to tell from the damage whether it was intentional or not," he said. "[There] could be a wealth of information potentially gathered in addition to the location of the bike."
Garrett said the bike could have paint from the suspect's vehicle on it or DNA from Shunick or the suspect.
Authorities are also searching for the drivers of three cars -- a white pickup truck, a four-door Chevy and an older model sedan -- that were spotted on security footage around the same time and in the same area where Shunick was last seen.
"The vehicles we're looking for are just vehicles of interest, not necessarily suspects," Mouton said. "We know those vehicles were in the area and in the immediate area."
When asked whether police had been able to contact any of the vehicles' drivers, Mouton said, "Not as of yet, but we are working on some things as of now."
Garrett said, "It's very important for them to locate and identify the drivers of the vehicles that were on surveillance tape because one of them could be the suspect, but, equally important, they could be witnesses."
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