A nationwide operation against illegal telecom base stations is progressing well with nearly 1,800 suspects detained, said China's top cyber security task force here Tuesday. From February, when the operation began, to April 24, police detained 1,783 suspects operating illegal base stations or using them to commit fraud, said the central leading group of Internet security and informatization in a statement. The group is led by President Xi Jinping. An illegal base station can cut communications between mobile phones and legal base stations then send disguised text messages. This has facilitated fraud and illegal advertising, according to the statement. Illegal base stations not only infringe privacy and property rights but disturb public order, the statement said. Besides operators of illegal base stations, authorities have pursued hardware suppliers, Internet service providers and advertisers, deleting or blocking most of information sent. "Phone fraud and illegal advertising by text message have been specifically targeted," the statement said. The operation is set to end in June. Until then, authorities will continue wiping out illegal base stations and targeting hardware and software suppliers, as well as websites that promote the business, the statement said. The government welcomes public tipoffs, it said.