The Royal Gibraltar Police (RGP) said it was investigating the claim that “a small number of missiles” were thrown at Guardia Civil officers carrying out stringent checks on traffic at the border on Wednesday afternoon.
Up to 8,000 Spaniards living mainly in the nearby towns of La Linea and Algeciras work in Gibraltar and have been caught up in regular long queues caused by checks imposed as part of a diplomatic spat with Britain.
An RGP spokesman said it received an “unofficial report” from the Guardia Civil about missiles being thrown at its officers from the motorcycle lane, as well as verbal abuse.
“This has allegedly taken place at the peak of extensive queues to exit Gibraltar which at their height reached four hours,” he said.
“The alleged missile throwing is reported to have come from the area of the motorcycle lane which at the time was full of cross-border workers unable to return home.
“It came after insults and abusive comments were directed at the Guardia Civil.
“The RGP is, notwithstanding the number of RGP officers present at the frontier managing the traffic, unable to substantiate the complaint at this time.
“The matter is under investigation.”
Chief minister of Gibraltar Fabian Picardo met Foreign Secretary William Hague in London on Wednesday to discuss the border dispute with Spain in talks the Foreign Office said reaffirmed “the strong bonds” between the UK and Gibraltar and the UK’s commitment to stand by its people, describing the border delays as “unacceptable”. Mr Picardo is due to meet Prime Minister David Cameron today.
The traffic checks, which have led to long delays on both sides of the border, were introduced by the Spanish government in protest at an artificial reef sunk off the British Overseas Territory.
The Spanish say the 74 concrete blocks on the seabed disrupt an area used by its fishing boats, while the Gibraltarians say it was a necessary environmental measure.
The row, which started at the beginning of this month, has gone all the way to the European Commission and continued to simmer in recent days.
The Gibraltar government accused Spain of introducing an export ban on construction materials destined for the enclave.
It threatened legal action and an official complaint to the European Commission if the “illegal and anti-European” restrictions are not lifted.
Last Friday a group of divers from a Spanish Guardia Civil unit entered Gibraltarian waters and inspected the concrete reef.
Pictures posted online showed them unfurling a Spanish flag at the seabed.
The move was criticised by the Gibraltar government, which said the “serious incursion will not assist” in de-escalating the present tensions.
A regional politician also sparked anger by reportedly posting online a cartoon showing Spanish troops in Gibraltar and the Spanish flag flying over the Rock.
Last week more than 40 commercial Spanish boats staged a protest over the reef before being removed from Gibraltarian waters by police and Royal Navy patrol boats.
European Commission observers are to visit the border crossing to assess the legality of the checks on traffic after Spanish Prime Minister Mariano Rajoy agreed to allow them access after talking to commission president Jose Manuel Barroso.