Authorities say they are investigating a letter purportedly sent by fugitive Joseph Jakubowski that threatens violence at Wisconsin churches on Easter Sunday.
Police in Waukesha County say the letter was sent through the U.S. Postal Service and mentions churches in the Sussex area, about 25 miles northwest of Milwaukee.
The Rock County Sheriff's Office says the letter is being analyzed and "its authenticity is in question."
A manhunt has been underway since police say Jakubowski robbed a gun store in Janesville, Wisconsin on April 4.
They have warned that the fugitive is considered armed and dangerous and the public should not approach him.
