Johannesburg - Attacks on Cosatu unions and its officials should be taken seriously, Numsa president Cedric Gcina said on Friday.
"These are not small matters," Gcina said at the National Union of Metalworkers of SA's (Numsa) 26th anniversary celebrations in Johannesburg.
"It is time the African National Congress government take these small, but consistent attacks on offices and homes of union officials seriously," he said.
Gcina said there was an unexplained attack on the Numsa offices in the Johannesburg CBD on Monday, and that the house of Congress of SA Trade Unions (Cosatu) spokesperson Patrick Craven, whose wife works at Numsa, was recently burgled.
"It becomes hard to explain that a drunk person threw stones at Numsa offices at 2am, breaking windows and destroying Numsa signage," he said.
"These incidents are very worrying."
Gcina said the union would continue to reject the National Development Plan in its current form.
"The content that is in the NDP is not going to help workers and the country. It does not represent what the founders of this union strived for."
At the celebration, the union also launched a recruitment drive, aiming to increase its membership from 320 000 to 400 000 members by 2016.
Numsa organises in the tyre, rubber, motor, auto and engineering sectors, and at the power utility, Eskom.
Cosatu general secretary Zwelinzima Vavi is expected to speak at the event.