Sri Lanka secured a semifinal spot in the ICC World Twenty20 after defeating New Zealand by 59 runs in a Group I match played at Zahur Ahmed Chowdhury Stadium, in Chittagong on Monday.Earlier in another match, Netherlands upset England by 45 runs in a Group One league match. South Africa have already booked their semi-final berth from this group with six points. It may be recalled that India have already qualified for the last four stage from Group Two. The result of Tuesday's match between the West Indies and Pakistan at Mirpur, will decide the second semi-finalist from this Group Two.