Pipe bombs have exploded outside two homes in Londonderry in linked racist attacks, police said.
Officers are treating the incidents in the Waterside area in the early hours of the morning as hate crimes. Nine people escaped injury in the blasts.
Shortly after 1.35am, officers received reports a pipe bomb-type device had exploded outside a house in the Lapwing Way area.
No damage was caused to the property. Four adults and one child who were in the house at the time were not injured.
Around the same time another pipe bomb exploded outside a house in the Lincoln Court area.
The front door was damaged but the four adults inside the property were not injured.
Remains of the devices have been taken away for forensic examination.
Police have appealed for anyone with information about the attacks to come forward.
SDLP Assembly Member for Foyle Pat Ramsey said two Romanian families had been targeted.
"It appears that this appalling attack on homes in Derry was racially motivated; this is a very disturbing development," he said.
"The devices used were viable and this disgraceful attack must be condemned by all in our community.
"My thoughts are with the families who have been targeted and endured such a terrifying experience during this unacceptable attack.
"We must value, respect and accept our migrant community living in the city. Migrant workers are making a significant contribution to our economy and our society.
"I expect the fullest police investigation into this attack. Those responsible must face the full rigour of the law.
"I call on anyone who may have information about this to contact the PSNI."