State police were back at the trash facility in Hartford Monday, searching for evidence of Jennifer Dulos, as the case enters its fourth week.

The 50-year-old mother of five dropped her children off at school on May 24 and has not been seen since. Almost four weeks later, there is still no sign of her.

News 12 spoke with Leo Chupron, a 20-year veteran of the Hartford Police Department. Chupron isn't involved in the investigation but has been following the case.

"There's a lot of strategy here," Chupron said. "Don't think the state police are going to just back away from this. They put their name on it, they own it now."

Police found blood splatter in Jennifer Dulos' New Canaan home and evidence of a physical assault. Her estranged husband, Fotis Dulos and his girlfriend, Michelle Troconis, have been arrested and charged with tampering or fabricating evidence and hindering prosecution. Both pleaded not guilty last week and have posted bond.

Arrest warrants show Fotis Dulos and Troconis were believed to be captured on surveillance video throwing out trash bags at more than 30 spots in Hartford.

Tests confirmed Jennifer Dulos' blood was in some of the bags recovered from the trash. The search for evidence continued Monday at the MIRA trash plant in Hartford.

The state police dive team has also been searching two ponds in Avon. There have also been multiple searches at Waveny Park.

Troconis is due back in court on July 18, while Fotis Dulos is scheduled to appear in state superior court in Stamford on Aug. 2.

As of Monday, police have received over 740 tips and 80 surveillance videos from the public, but police say they are looking for more. Anyone who may have information in the disappearance of Jennifer Dulos is asked to call police.