ALTAMONTE SPRINGS, Fla. — Crews continue to try to determine the cause of a sinkhole that opened beneath an Altamonte Springs condominium building Tuesday, forcing 13 residents to evacuate, the Altamonte Springs Police Department said Monday.
[ Read: Crews try to fill sinkhole that forced 13 people to evacuate from Altamonte Springs condos ]
The hole, which grew to 20 feet wide and 20 feet deep, opened at about 6 p.m. Tuesday at the Royal Arms Condominiums near East Altamonte and Palm Springs drives.
Police had originally said Friday that the sinkhole was caused by testing done by a geology firm, but then they said Monday that the official cause is unknown.
[ Read: Holey Florida! 9 facts about sinkholes ]
"Any cause determination will be made by the professional engineers conducting the investigation," said Michelle Sosa, a police spokeswoman.
She said the hole was filled and that residents were allowed to return to their homes Monday after crews conducted structural evaluations.
[ Read: Sinkholes: Warning signs to look for to protect homes ]
See drone footage of the sinkhole before it was filled:
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