“We are looking for further clues in the case, and for the sake of the continued investigation we are currently unable to comment further on the case,” Copenhagen police inspector Jorgen Skov said in a statement.
Officers in bulletproof vests, assisted by police dogs, searched several residences in the Danish capital.
Police are still in the process of clarifying the movements of the perpetrator and others who were involved in February’s shootings, according to Skov.
The gunman, 22-year-old Omar Abdel Hamid El-Hussein, was fatally killed by police following the attacks. Several people suspected of aiding the gunman have been arrested.