A protest outside Belfast City Hall, linked to the Union flag controversy, has passed off peacefully.
Several hundred people took part in the demonstration and the PSNI mounted a huge security operation.
Since Belfast City Councillors made their controversial decision to alter policy on the flying of the Union flag, 127 police officers have been injured and 175 people have been arrested.
On Friday night at Newtownabbey, rioters threw 12 petrol bombs at riot police.
Sporadic trouble has erupted for eight weeks linked to Belfast City Council's decision to only fly the flag on designated days, such as royal birthdays.
A series of protests blocked roads around Belfast, but most were non-violent and police said the routes have reopened.
The PSNI spokesman said a suspicious device was thrown at a police vehicle in the Cloughfern Avenue area of Newtownabbey during an operation linked to flag protests.
He said ten to 12 petrol bombs were thrown at police in Newtownabbey and a further 19 seized by officers and taken for forensic examination.
"Police came under attack from crowds throwing stones, bottles and petrol bombs following an earlier protest in the area," the spokesman added.