A pensioner has admitted threatening to kill Prime Minister Theresa May among a series of threats.

Isabella Jackson also sent white powder labelled "death" to police officers and made bomb threats to Edinburgh Airport and King's Cross Station and Harrods in London.

The 72-year-old, of Braehead Gardens in Buckhaven, Fife, faces jail as her offences started only months after she was released from a two-year sentence for threatening to blow up a plane carrying then-US president Barack Obama.

Jackson pleaded guilty at Kircaldy Sheriff Court to behaving in a threatening and abusive manner towards then-home secretary May on November 24, 2014, and towards Fife Police CID between January 4 and January 17 this year.

The pensioner threatened to kill Theresa May through an e-mail sent to Ms May's aides in 2014 from her home in Fife.

Then, in January this year, she sent another e-mail making bomb threats against Edinburgh Airport and Kings Cross Station and Harrods in London while on bail for the Theresa May threat charges.

Jackson also emailed Police Scotland's Professional Standards Department in Aberdeen and the Professional Standards Department of the Metropolitan Police in London, informing them of the "bomb" at Harrods.

The court heard Jackson "sent information with the intent of inducing in them a false belief that a bomb or other thing likely to explode or ignite" was present at the upmarket retailer as well as at the two transport hubs.

Shortly after the bomb threats Jackson, sent a package of white powder labelled "death" by post to the Levenmouth CID office on Sea Road in Methil, which sparked a major incident.

Firefighters and ambulances went to the scene and a major investigation was launched which led cops to Jackson.

Sheriff Grant McCulloch deferred sentence until later this month for social work background reports and called for a forensic risk assessment on Jackson.

She will be remanded in custody and ordered a hearing on a serious crime prevention order.

In 2015, Miss Jackson was also involved in an incident when she sent a message, which she knew to be false, stating that a Fife Council worker had died.

The court was told that "for the purposes of causing annoyance, inconvenience or needless anxiety" to Susan Johnston she sent a message stating that Ms Johnston had died.

Jackson was given a two-year prison sentence at Dunfermline Sheriff Court in 2013 after sending email threats to the US Embassy in London claiming there was a bomb on a US plane and that President Obama "was to be killed".

In the emails, she also told US Embassy staff that there would be explosions at the building on Grosvenor Square in London.

Six months later she also sent similar threats to the US embassy in Paris.