Dissident republicans have been blamed for a trio of bomb alerts outside the homes of PSNI officers' parents in Londonderry.
The first took place in Shantallow on Wednesday when an elaborate device was found close to the property of an officer's parents.
In the early hours of yesterday there was a similar alert close to the home of the parents of a second officer at Inishowen Gardens in Creggan.
And later yesterday the elderly parents of a third officer were targeted when a suspect device was found at their front door on Lone Moor Road in the Brandywell.
In all three incidents dozens of residents had to be evacuated from their homes for several hours and areas around the scenes of the alerts were sealed off.
Community worker Kathleen Bradley, whose parental home at Lone Moor Road was at the centre of yesterday's third alert, is sister to a police officer.
"I think these incidents are uncalled for and totally unjustifiable," she said.
"I do not think anyone would want to see their elderly parents suffer in this sort of situation.
"I apologise to our neighbours, who have also had to suffer this disruption to their lives.
"I spoke to my mother this morning and she said she and my father found the device at the top of the steps outside their front door.
"This should not be inflicted on elderly people, who should be allowed to live out their retirement, after long and productive lives, in peace. It causes immediate fear and anxiety, not only to those targeted in this way but also to their neighbours and wider family members.
"What happened to my father and mother today is absolutely disgusting and it is a sad reality and a sad reflection on our society that we are still dealing with these sorts of things in 2018."
Mark Lindsay, chair of the Police Federation, which represents rank-and-file officers, said the deliberate intimidation was the lowest form of cowardice.
"The message of those responsible is totally outdated," he said.
"These people affected are the elderly parents of children who have stepped up to the plate by joining the PSNI to make our society a better place for us all.
"Their actions are in stark contrast to the decisions taken by men and women to join the PSNI for the betterment of us all."
Ulster Unionist policing spokesman Alan Chambers said the spate of attacks was the work of cowards.
He said: "Attacks such as this are designed to intimidate other young people in the area from coming forward and joining the PSNI. This is a cynical attempt to prevent Catholics from joining the police and it must be resisted."
Foyle DUP MLA Gary Middleton also condemned the alerts, which he said were designed to instil fear and terror within the community.
"These devices and elaborate hoaxes have been planted deliberately by dissident republicans. Those people are thugs," he said.