Mankato police have locked down the area around Echo St.
An emergency text alert sent shortly after 9:30 a.m. asked residents to shelter in place due to emergency police activity.
A Mayo Clinic spokesperson said the hospital campus was part of the lockdown, but patients would still be able to access the facility. She noted that everyone would be screened at the door.
A Bethany Lutheran College representative said the college campus was also on lockdown out of an abundance of caution.