City officials said three of the people who died were homeless. One was a non-Manchester resident who died in a hotel. The others died in homes.
NEW HAMPSHIRE CONSIDERING 'MENTAL HEALTH' DAYS FOR K-12 STUDENTS
Officials are waiting for toxicology reports for more answers.
New Hampshire officials are forming a team to track drug overdose deaths in the state.
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"What we did today is go through the seven individual cases trying to find a common denominator," said Anna Thomas, Manchester public health director.
The Manchester Police Department has activated a daily overdose monitoring system to try and track the deaths and eventually send the teams out to hot-spot areas.
"The idea is to flood those areas with resources to really try to educate people in the area," Thomas said.