Armed police have raided properties in the area of Middlesbrough where a woman and her seven-year-old niece were killed in a suspicious house fire.Officers armed with rifles were seen training their weapons on homes in Burns Road, Grangetown in the early hours of Monday.Eyewitnesses said one person was arrested and a vehicle was seized.The raid follows a week of escalating violence thought to be linked to a postcode gangland war between two factions of a local organised crime group - and a deadly motorway crash that killed two police officers and five youths.The young men and teens in the car were said to have been pursuing rival gang members shortly before driving the wrong way down the A66 and smashing into PC Matthew Blades and PC Tom Clough. The dead youths are Michael Cahill, 23, Jakub Matusiak, 23, Makai Saddington, 18, Theo Rae, 17, and Cole Worthy, 17, four of whom had lengthy criminal records ranging from theft, harassment and assault to drug dealing and knife possession.The small area of Middlesbrough also saw a fatal house fire last Wednesday, which killed Natalie McDonald, 34, and Valentina Foster, seven. Although thought to be related to gangs in the area, the blaze is not being directly linked with last Saturday's crash at this stage. Armed police raided two homes in Grangetown, Middlesbrough in the early hours of this morning following a week of violence Officers were seen training their weapons through the doors of one home. Cleveland Police is yet to comment on the raids Multiple police vehicles were parked in Burns Road in Grangetown - the area of Middlesbrough that has been rocked by violence in recent days A 31-year-old man who was arrested on suspicion of murder has since been released without charge. A second man, 23-year-old Jaden Wright, continues to be questioned by police after appearing in court on Saturday charged with grievous bodily harm and strangulation in relation to an incident in Grange Farm Road on Tuesday August 25.Fires were seen in local fields after at least five cars were set alight at a balloon release in memory of one of the crash victims.Anna Turley, the Labour MP for Redcar, who is also a Home Office minister, told BBC News: 'Seeing illegal bikes and quad bikes rampaging, and fires and fireworks being set off only heightens people's sense of fear and lawlessness.'While I understand people are grieving and upset, we cannot allow illegal activity to be excused and unchecked.'PC Blades and PC Clough were remembered with a minute's applause ahead of Middlesbrough and West Bromwich Albion's Championship match on Saturday, while PC Blades' sons walked out as mascots with Manchester United yesterday.Supporters also paid their respects at Seaton Carew FC's game against FC Hartlepool. PC Blades had been a junior coach for both teams.That the five teens they were out on the road is thought to be linked to a ram-raid on Cole Worthy's father's home. His father, 39-year-old Gye Worthy, has no links to criminality. PC Matthew Blades, 37, was killed when his police vehicle was struck by a Volkswagen Passat travelling the wrong way down the A66 near Middlesbrough PC Tom Clough, 38, also died in the crash, which occurred around 10 seconds after a police pursuit of the Volkswagen was called off Valentina Foster, seven, and her aunt Natalie McDonald, 34, died in a house fire on Wednesday The scene of devastation at the home in Grangetown where Ms McDonald and young Valentina died in a fire last week