The operators of a gas plant in Fife have apologised after further unplanned "flaring" began at the weekend.

ExxonMobil said the issue was caused by a pump at the Fife Ethylene Plant at Mossmorran, with flames and smoke seen at the site.

The incident occurred just a few weeks after ExxonMobil Chemical and Shell UK were issued with a final warning by the environment watchdog Sepa.

The regulator said the impact of unplanned flaring last June was "preventable and unacceptable."

ExxonMobil, an energy giant based in Texas, apologised to residents said it was not possible to predict when the current flaring would end.

Sonia Bingham, manager of the Fife Ethylene Plant, said: "Good progress is being made as our maintenance team and specialist supplier work around the clock to resolve the issue.

"The failed pump is being repaired utilising the available spares needed and we will then commence the commissioning of the pump into operation."

Sepa said it was organising a full response to the incident.

It issued a statement saying: "Flaring remains an important safety mechanism and is permitted through licence conditions.

"However, in response to the flaring, which began in the evening of Saturday 19 May, Sepa has mobilised a full response.

"The response includes both air quality and noise monitoring to assess the local impacts."