More than 100 people are believed to have been infected by coronavirus at a wedding early this month in the northern Mexico border city of Mexicali, authorities said.
About 300 people attended the October 3 nuptials of a soap opera actor and the daughter of a businessman, health secretary of Baja California state Alonso Oscar Pérez Rico said on Monday (local time).
Mr Pérez Rico told local media that there were apparently no masks or temperature checks at the event and the organisers also did not have permission to hold an event of that size during the pandemic.
He said authorities are investigating whether anyone attended the wedding knowing they had Covid-19 or were infected by the virus.
In some states in Mexico, knowingly infecting someone with a disease is a crime.
Photos published in local media show wedding guests dancing together without masks.
Mexicali has seen almost half of Baja California state's 21,800 coronavirus cases. Nationwide, Mexico has recorded almost one million confirmed cases and about 86,300 deaths.
Officials fear more infections could be sparked by upcoming celebrations, especially during the Day of the Dead holiday which runs from November 1-2, when families visit relatives' graves.
Some local authorities have said they will discourage or limit such gatherings.
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