The latest three arrests are a 26-year-old man and a 19-year-old man from Eastleigh and a 34-year-old man from Southampton. They are being questioned on suspicion of causing an explosion likely to endanger life.
Police investigating an explosion outside a house on Chadwick Road in Eastleigh at the weekend have arrested three more people.
This brings the total number of people arrested in connection with the incident to six. Two have been bailed until June while enquiries continue.
An 18-year-old Eastleigh man arrested earlier is still being held after a Magistrates extension was granted to allow officers extra time to question him.
Detectives are continuing their investigation and appeal for witnesses to the explosion which occurred at around 2.30am, Saturday, April 10. All information will be treated in the strictest confidence.
A home made explosive device was placed on the driveway which caused extensive damage to three vehicles.
Police are reiterating they are not treated this as a terrorist incident or domestic extremism incident. A number of officers are working on the investigation and enquires are continuing.
Officers from the local Safer Neighbourhoods team are continuing to put on extra patrols in the area to speak to residents and offer reassurance.
Anyone with information about the incident is asked to contact The Operation Birdline office at Eastleigh Police Station on 101. They can also call the anonymous Crimestoppers charity on 0800 555 111.