The two cases happened in the early hours Cambridge Road and Burnaby Road.
Police Officers In Hospital After Southampton Arson Attack
Two police officers have been taken to hospital after a deliberate fire on the 12th floor of a Southampton block of flats.
They've been treated for breathing in smoke, along with another officer at the scene.
Hampshire Constabulary responded to a call shortly after 7.30pm yesterday evening (Tuesday 6 January) from flats on Warburton Road in Thornhill. More than 70 firefighters were also called out.
Some neighbouring residents had to evacuate as a temporary precaution, but were allowed to return to their properties a short time later.
Police say a 55-year-old woman was arrested last night on suspicion of arson and is still being questioned in custody.
The police officers' conditions are not believed to be serious.
Hampshire Fire and Rescue said the fire on the 12th floor involved the front door of a flat, with smoke damage to the 12th floor landing. 10 fire appliances attended from Hightown, St Marys, Hamble, Eastleigh, Redbridge, Cosham, Bishops Waltham, Fareham and Botley fire stations, along with the special equipment unit from Redbridge fire station. A total of 68 firefighters and eight officers attended.
A police spokesperson said:
"We would like to thank members of the public for their co-operation.
"Hampshire Constabulary is investigating the cause of the fire, which is being treated as suspicious at this time.
"We are appealing for any witnesses, particular anyone who saw or heard any disturbances inside the block of flats after 7pm on Tuesday."
Witnesses or anyone with information are asked to contact CID at Shirley police station by phoning 101. Mini-com users can phone 18001 101. Information can be given be anonymously by phoning the independent Crimestoppers charity on 0800 555 111.
Lewis Hine - who has a brain tumour - posted an inspirational film about his life, on his 16th birthday last week.
One of the men's targets was Ernest Jones in Portsmouth, taking £57,000 worth of watches.
Detectives Searching For Dash Cam Footage Around Gilpin Close.
Recently Played Tracks
Now playing: Non-stop hit music
Deposit £10 to get a £40 Welcome Bonus - That's £50 to play bingo, slots and more!*
Over 50 tracks to make you feel-good. New album out now...
Find your local four day weather report here.
What's happening on the roads where you are?
Make Heart the soundtrack to your day and you could be a winner with great prizes up for grabs throughout the day.
Find out more about some of the companies advertising on Heart.
Get some great ideas on how to advertise your business on radio, online and on mobile.