Egyptians back constitution in first vote

Rights groups raise questions about polls opening late and bribery

Egyptians voted narrowly in favor of a constitution shaped by Islamists but opposed by other groups who fear it will divide the Arab world's biggest nation, officials in rival camps said on Sunday after the first round of a two-stage referendum.

Next week's second round is likely to give another "yes" vote as it includes districts seen as more sympathetic toward Islamists, analysts say, meaning the constitution would be approved.