Security guards have been parachuted in to protect library staff and users amid concern for public safety after anti-social behaviour blighted the normally serene institution.

One alleged assault at the Central Library in Edinburgh was the trigger for the introduction of dedicated door staff who are vetting people as they enter.

A 38-year-old man has appeared in court over the incident which took place on a Saturday afternoon at the start of the month.

Edinburgh City Council, which runs the library, said it is the first of its 28 public libraries across the city to be subject to such security measures.

It comes after concern over the number of drunks abusing the Central Library premises on George IV Bridge in the Scottish capital.

Some have been asked to leave after being found slumped over reading desks sleeping in a stupor.

Library users said anti-social behaviour had increased and was leading to some customers avoiding the library all together because of the disruption in the facility, the city's oldest public library building, which opened in 1890.

Details of the incident are not yet clear but it prompted council chiefs to take the unprecedented step of bringing in security staff to "re-assure staff and customers".

A spokeswoman for Edinburgh City Council said: "In response to an isolated incident at the library recently, security measures have been brought in to re-assure staff and customers and to promote a positive use of the facility.”

One student said: "It was pretty bad, they were coming in just for a sleep .

"It was intimidating for people studying and the staff shouldn't have to deal with rowdy drunks looking for somewhere out of the rain."

The move comes after new figures reported last month revealed incidents in libraries in recent years have led to scores of people being banned from the city's public libraries.

It was found that vandalism of library property, drunken behaviour and visitors abusing staff when woken are among incidents recorded at public libraries across the capital.

Airguns were fired in one library and a number of people were reported to police over alleged acts of violence.

Other incidents have included alleged attempted fire-raising and racist abuse.

A total of 72 people were told to stay away from libraries for up to a month between April 2012 and March 2015.

The Chartered Institute of Library and Information Professionals in Scotland (CILIPS) said it was unaware of the incident at Central Library and could not comment, but it reportedly said earlier the city council had a legal obligation to ensure a safe working environment, adding: "Libraries, in common with other public services, occasionally experience anti-social incidents.

“The employers’ legal duty to provide a safe working environment has additional support from CILIPS through its advocacy and support for training for front line library staff and their managers.”

A spokesman for Police Scotland said officers were called to the library on March 5 over an incident involving allegations of assault.

“Police in Edinburgh were called to a business premises on George IV Bridge at around 2.40pm on March 5 following a report of a disturbance.

“A 38-year-old man was arrested for the assault of a man, also aged 38.

“He appeared at Edinburgh Sheriff Court on March 7.”