Councils across the area are shoring up their defences to stop caravan convoys parking on public land.
It comes amid the surge of camps having sprung up across Portsmouth, Fareham, Wickham and Havant in the past week.
The latest appeared on Southsea Common on Tuesday, with about a dozen caravans forcing their way past defences.
Portsmouth City Council has ordered travellers to leave and insisted it will begin legal proceedings to evict them if they remain.
Meanwhile in Fareham, anger reached boiling point last night – with Hampshire Constabulary coming under fire for its handling of travellers at Cams Alders Recreation Ground.
A group of 12 vehicles stormed the site on Friday, forcing the postponement of children’s football matches over the weekend.
In a furious outburst to The News, borough council leader Councillor Sean Woodward slammed police for a ‘lack of action’.
‘Police have failed dismally,’ he said. ‘The travellers are now trespassing on council land but the police are doing absolutely nothing.
‘They have already got the powers to do something – they just aren’t using them. It’s appalling.’
The Tory leader revealed a council worker was allegedly assaulted while trying to defend the public plot.
The male worker was ‘surrounded’ by seven vehicles on Friday and verbally abused before his ride-on lawn mower was rammed by a vehicle, Cllr Woodward said.
‘An innocent member of staff has been assaulted,’ the council chief added. ‘These actions are absolutely appalling and unforgivable.’
Hampshire police has investigated the incident with a spokesman saying it had ‘now been filed’.
The force added the arrival of travellers at the field did not cross the threshold for police to take action to remove them using section 61 powers.
Inspector John Stribley added: ‘In circumstances where we utilise such powers, Hampshire Constabulary will always ensure that we balance the needs and rights of all our communities with actions that are proportionate, lawful and necessary. To that effect we have used police powers seven times in the last 10 days for problematic groups.’
Elsewhere, Cllr Gerald Vernon-Jackson, leader of Portsmouth City Council, is demanding Whitehall gives more power to authorities to speed up the process of removing illegal encampments on public land.
He added: ‘We have spent a fortune going to court to remove illegal encampments and clearing up after them. It’s incredibly frustrating.
‘I don’t want to fence the common but the government needs to get itself in order and give us the power to make sure illegal encampments can be removed from public land... they’re just not interested.’
In Havant, the borough council is preparing to install bunds and swales in Mengham Park, which last week saw dozens of saplings trampled by travellers.
Council leader Alex Rennie insisted the work would help to save thousands on costly court and clean-up fees.
He added: ‘We feel the frustration but we are taking firm action to ensure sites are defended.
‘While it is frustrating to use taxpayers’ money to defend sites it is worthwhile and will save money in the long run.’
Elsewhere, on Tuesday a group of 25 caravans arrived at Shedfield Common near Wickham.