Singer and business woman, Rihanna. (Picture: Instagram)

Rihanna's Hollywood home was monitored by a hovering helicopter after an alarm was set off at her mansion on Monday.

The 'Wild Thoughts' singer's pad was kept under surveillance by the Los Angeles Police Department (LAPD) whilst they determined what triggered the security device to sound off.

According to TMZ, the 30-year-old singer was not at the property when the disturbance took place, and fortunately it turned out to just be a false alarm.

Despite this, cops remained outside the property for extra precaution after an intruder allegedly spent the night in Rihanna's home in May.

Police were sent to the 'Diamonds' singer's abode on that occasion after they were alerted to the fact someone was inside the property and may have tampered with the burglar alarm system, and when officers arrived, they discovered 26-year-old Eduardo Leon, who appeared to have been there for some time.

Sources said at the time that police ordered the man to come outside, and though he did, he was tased while being detained, though it is unclear why.

The man, from Orange County, was arrested for felony stalking and held on $150,000 bail.

It wasn't clear if the man took anything from the house, or how he gained entry.

However, he was later charged with the stalking charge and burglary.

The incident came hours after Rihanna announced who will host her Diamond Ball this year.

'Insecure' actress Issa Rae will take centre stage at the annual fundraising gala - which benefits the 'Work' hitmaker's own Clara Lionel Foundation - on September 13 in New York City, while 'This Is America' hitmaker Childish Gambino will perform for the guests.

Rihanna said in a statement: "Issa Rae and Childish Gambino were the dream duo for the fourth Annual Diamond Ball and they're coming!!! We are honoured and grateful to have them help us celebrate the Clara Lionel Foundation this year."

The black-tie gala will also see Hugh Evans, the CEO of Global Citizen who co-founded the Global Poverty Project in 2008, honoured with the Diamond Ball Award in recognition of his humanitarian work.