Egyptians were voting today on a proposed constitution that has polarized their nation, with President Mohammed Morsi and his Islamist supporters backing the charter, while liberals, many secular Muslims, and Christians oppose it.

With the nation divided by a political crisis defined by mass protests and deadly violence, the vote has turned into a dispute over whether Egypt should move toward a religious state under Morsi's Muslim Brotherhood and a radical Salafi bloc, or one that retains secular traditions and an Islamic character. About half the nation votes today and half next week.

Morsi, whose narrow win in June made him Egypt's first freely elected president, cast his ballot at a school in the upscale Heliopolis district. He did not speak to reporters, but waved to dozens of supporters who were chanting his name outside the polling station. Highlighting the tension in the run-up to the vote, nearly 120,000 army troops were deployed to protect polling stations. A radical Islamist group also said it will send its own members to defend the stations alongside the army and police.