Muslims mark end of Ramadan with Eid prayers, though wars in Gaza, Syria cloud celebrations

An Egyptian child plays as Muslims pray Eid al-Fitr prayers, marking the end of the Muslim holy fasting month of Ramadan at Al-Azhar mosque, the highest Islamic Sunni institution, in Cairo, Egypt, Monday, July 28, 2014. (AP Photo/Amr Nabil) (The Associated Press)

Indonesian Muslims offer Eid al-Fitr prayers at the port in North Jakarta that marks the end of the holy fasting month of Ramadan in Jakarta, Indonesia, Monday, July 28, 2014. (AP Photo/Mark Baker) (The Associated Press)

Bangladeshi Muslims living in Malaysia offer a prayer during the first day of Eid al-Fitr, which marks the end of the fasting month of Ramadan in Kuala Lumpur, Malaysia, Monday, July 28, 2014. (AP Photo/Lai Seng Sin) (The Associated Press)

Millions of Muslims across the world are celebrating the first day of the Eid al-Fitr holiday, which marks the end of the monthlong fast of Ramadan.

Families dressed in their finest clothes and children carried their new toys as they headed to mosques early Monday morning to observe traditional Eid prayers.

But the mood was dark for millions of people affected by the Syrian civil war, the Gaza war and the militant advance in Iraq.

Muslims in Indonesia, Malaysia, the Philippines, across the Middle East, Europe and the U.S. are celebrating Eid Monday. Millions in India, Pakistan and Morocco are still fasting and will likely celebrate Eid on Tuesday.

Muslims use a lunar calendar and a moon-sighting methodology that can lead to the month of fasting ending on different days.