ANGOLA, one of the world’s most heavily mined countries, on Thursday finally joined the Maputo conference of parties to the Ottawa Convention banning landmines. A delegation headed by deputy minister of external relations Toko Serao arrived in the Mozambican capital amid speculation that its failure to turn up was connected to its continued violation of the Ottawa convention. The conference has criticised both the Angolan government and Unita rebels for laying new mines in the war-torn country. The counsellor from the Angolan embassy in Maputo attended the opening session on Monday but did not return, leaving Angolan seats vacant until Thursday.