The warning came just hours after a 52-year-old prison officer was injured when an explosive device detonated under the van he was driving shortly after leaving his home in Northern Ireland's main city, Belfast.
Stephen Martin, a senior officer in Northern Ireland's police force said he was "very worried" about the threat ahead of the commemoration on March 27 of the revolt that paved the way for Ireland's independence.
"There are people within dissident republican groupings who want to mark the Easter 2016 100th anniversary in an entirely more sinister way, who want to kill police officers, prison officers or soldiers," Martin said in a video on Facebook.
A 52-year-old prison officer was injured today shortly after leaving home on his way to work when an explosive device detonated under the van he was driving in Northern Ireland's main city Belfast.
More From This Section
Martin said his injuries were "not life-threatening" but added: "This could have been a fatal attack."
Northern Ireland's First Minister Arlene Foster and her deputy Martin McGuinness, a former leader of the Irish Republican Army (IRA), condemned the incident as "despicable and shocking" in a joint statement.
"The perpetrators offer nothing but hatred and fear," they said.
Some 3,500 people were killed during a mostly sectarian conflict in Northern Ireland that lasted more than three decades.
Much of the violence was brought to an end by the 1998 Good Friday peace agreement that created a power-sharing coalition in the province.