"The public will see an increased police presence at iconic sites, our transport networks and where large numbers of people congregate," Hamilton said in a PSNI statement, uploaded to their Twitter account.
According to the chief constable, the deployment of troops ordered by UK Prime Minister Theresa May will not apply to the region.
Earlier in the day, UK Home Secretary Amber Rudd said that up to 3,800 soldiers could be deployed in UK streets to assist police as the level threat across the country was raised to "critical."
An explosion at Manchester Arena left 22 dead and wounded dozens of others. The police suspect 22-year-old Salman Abedi who died in the blast of having been a perpetrator. The Islamic State terrorist group, outlawed in Russia, has reportedly claimed responsibility for the attack.