Police say they don’t know when they’ll be done searching for evidence at Dellen Millard’s farm property in North Dumfries.

Officers, primarily from the Toronto Police Service, have been at the site since Monday in connection with the disappearance of Laura Babcock.

Babcock was last seen in Toronto in July 2012, while Millard’s farm first came to police attention this May as they investigated the death of Ancaster resident Tim Bosma.

Millard and Mark Smich are charged with first-degree murder in Bosma’s death.

After those charges were laid, Toronto police began looking closer at Millard in connection with the death of Babcock. According to police, the two had an unusual romantic relationship.

Phone records show that Babcock was in contact with Millard after she was last seen by her family.

Asked about the search, Toronto Police Chief Bill Blair told reporters police have yet to conclusively determine whether Babcock met with foul play and will continue to look for evidence at the farm.

“We are sufficiently concerned that we are investing the resources at the time to go and see if that evidence does exist,” he said.

“When we have something to report publicly, I’m sure that’ll happen.”

Officers were seen Wednesday using a light as they searched the upper level of the property’s barn, while another group used pitchforks to sift through straw closer to Roseville Road.

A blue forensics tent was set up at the site to protect evidence in case of rain, and police say their search warrant is usable for “as long as we need to finish what we’re doing.”