World Cup organisers in South Africa suffered a public relations embarrassment today when it was revealed the Colombian football team had belongings stolen at a five-star hotel.

Police said two hotel workers stole money from members of the Colombian team a day after they arrived for a friendly match against the host nation.

Police spokesman Eugene Opperman said the players' hotel rooms were cleaned while they were out training on Tuesday, and when they returned they discovered cash was missing.

Media reports say that $2,800 (£1,900) was taken from suitcases in the rooms but police would not confirm the figure.

Opperman said two employees appeared in court yesterday on theft charges. The Times of South Africa named them as Jeanet Mashimbyi, 29, of Maseru, Lesotho, and 25-year-old Johannesburg resident Lucky Mahlatsi.

The incident occurred at the five-star Hyde Park Southern Sun Hotel in the affluent northern suburbs of Johannesburg. The hotel will host Slovenia during the World Cup.

The Times said it understood the Hyde Park hotel management allegedly asked the police to keep the incident quiet, fearing bad publicity and cancellations before the World Cup.

Opperman told the paper: "It was an inside job. How do you police that? You cannot. They worked there everyday."

Egypt's football team was robbed of nearly $2,500 at their Johannesburg hotel during last year's Confederations Cup.

Security experts said such lapses raise questions over the procedures currently in place. Neil Thompson, operations director of red24, a private security firm with corporate clients at the World Cup, said: "It's embarrassing for top quality hotels. I would have thought the World Cup organisers would give strict instructions to the hotel managers and heads of security."

He added: "There's always a problem with cleaners in hotels. They're a migrant community and paid very little. The hotel manager needs to do a risk assessment process for all cleaners at high-profile events like this. They should not be allowed to take anything into the room and should be searched when they finish work."

He warned that more teams could suffer thefts during the tournament. "It's inevitable things will go missing. It's inevitable people will try to get information from hotel rooms to give to the press."

Organisers and police have given assurances this will be the "safest World Cup ever" but South Africa will be under unprecedented scrutiny because of its high rate of violent crime – on average 50 people are murdered each day.

Rich Mkhondo, spokesman for the World Cup organising committee, said: "It was a case of petty theft and swift action was taken, with two arrests made and two suspects having already appeared in court.

"This is a clear indication of how seriously the South African police authorities view criminal acts of any kind and also shows they are well equipped and prepared to deal with security matters during the tournament. We commend them for their prompt response."

Some analysts predict that the arrival of a multimillionaire sports stars in the midst of one of the most unequal societies in the world will be a recipe for trouble.

The anxieties were underlined today in a travel alert on South Africa issued by the US state department. It warned: "While driving, keep doors locked and windows closed, avoid having purses, phones, bags and luggage in plain view, and when stopping at intersections at night or in isolated locations, leave enough space in front of your vehicle for a quick exit.

"Be wary of street vendors at traffic lights, planted obstacles and staged 'accidents' that may be traps for unsuspecting motorists. Do not stop for cars with flashing lights unless they are clearly marked as police or emergency service vehicles. Park your car in secure, gated parking lots or garages wherever possible, and do not leave bags or valuables in plain view."

It added: "Travellers to South Africa should avoid carrying or displaying expensive items or wearing eye-catching jewellery, stay in a group, and avoid walking at night."

South Africa's top police officer, National Commissioner Bheki Cele, has said preparations have been given the "thumbs up" by international security agencies.

The security force includes 44,000 officers from the national South African Police Service who will be dedicated solely to the World Cup. An extra 10,000 personnel from metropolitan forces will boost the total force to 54,000.

"We won't be ready today and we won't be ready tomorrow, because we were ready yesterday," Cele said at a recent police show of force, where some of the $90m worth of new security equipment was paraded. The hardware included water cannon, helicopters, speed boats, jet skis, new high-performance police cars and heavy-duty emergency rescue vehicles.