A security alert at the law courts in Belfast ended after a reported suspicious package was found to be a legitimate delivery.
Staff had contacted police amid fears that the item was another letter bomb.
It is understood the package contained a number of batteries.
Police were contacted after the item was examined in a security scanner at the Royal Courts of Justice.
A PSNI spokeswoman later confirmed: "Nothing untoward was found."
Four explosive packages have been discovered in Northern Ireland in less than a week.
The latest security alert forced the evacuation of the courts in the Chichester Street area of the city centre.
Dissident republicans opposed to the peace process have been blamed for the spate of letter bombs.
None of the devices has detonated.
Yesterday, the seat of the Northern Ireland Executive at Stormont Castle was evacuated after a viable letter bomb addressed to Northern Ireland Secretary Theresa Villiers was found.
On Monday, a similar device was delivered to the offices of the Public Prosecution Service in Derry.
Late last week two explosive packages - one addressed to PSNI Chief Constable Matt Baggott and the other to one of his senior commanders - were intercepted at Royal Mail offices in Belfast and Lisburn.