Thousands of people across the world took to the streets to join celebrations to welcome 2018 on Sunday night. As the clock struck midnight, fireworks exploded and revellers rang in the New Year.

In India, New Year celebrations were observed at not only popular landmarks, but also temples, mosques and churches. Security had been heightened at most places across the country ahead of the celebrations.

Here are some pictures of the celebrations:

One of the first countries to welcome 2018, fireworks fill the sky over the Opera House in Sydney, Australia. (Image Credit: Saeed Khan/AFP Photo)
One of the first countries to welcome 2018, fireworks fill the sky over the Opera House in Sydney, Australia. (Image Credit: Saeed Khan/AFP Photo)
Fireworks explode behind Big Ben during New Year's Eve celebrations in London, Britain. (Image credit: Toby Melville/Reuters)
Fireworks explode behind Big Ben during New Year's Eve celebrations in London, Britain. (Image credit: Toby Melville/Reuters)
New Year celebrations at Ajmer Sharif Dargah in Rajasthan. (Image Credit: IANS)
New Year celebrations at Ajmer Sharif Dargah in Rajasthan. (Image Credit: IANS)
People attend a prayer event on New Year's Eve at Wat Nathom in Vientiane, Laos. (Image Credit: Xinhua/IANS)
People attend a prayer event on New Year's Eve at Wat Nathom in Vientiane, Laos. (Image Credit: Xinhua/IANS)

Security was heightened in Bengaluru after several women were allegedly molested along Brigade Road in the city on New Year’s Eve in 2016. The Karnataka High Court had directed the Bengaluru Police to ensure that there is no repeat of the mass molestation incidents in 2017.

The Bengaluru Police had installed large screens on Brigade Road and MG Road where where the movement of people was streamed live, The Economic Times reported. Everyone was frisked at the entrance with door frame metal detectors before entering the area. Police personnel, however, resorted to mild use of batons to control the crowd at Brigade Road, Bangalore Mirror reported.

Crowd takes pictures in front of the lit up Chattrapathi Shivaji Maharaj Terminus railway station in Mumbai ahead of New Year's eve celebrations. (Image Credit: Punit Paranjpe/AFP Photo)
Crowd takes pictures in front of the lit up Chattrapathi Shivaji Maharaj Terminus railway station in Mumbai ahead of New Year's eve celebrations. (Image Credit: Punit Paranjpe/AFP Photo)
People throng the streets of Chennai to ring in the New Year. (Image Credit: IANS)
People throng the streets of Chennai to ring in the New Year. (Image Credit: IANS)

Heavy traffic crippled Delhi on Monday as over 1 lakh people gathered at India Gate to participate in New Year celebrations. Earlier on Monday, the Delhi Traffic Police had warned that traffic near India Gate C-Hexagon was likely to remain heavy and that parking spaces will not be available around the area.

Youngsters celebrate on New Year's Eve on Sunday night in Mumbai. (Image Credit: IANS)
Youngsters celebrate on New Year's Eve on Sunday night in Mumbai. (Image Credit: IANS)
Sand Artist Manas Sahoo bids adieu to 2017 and welcomes 2018 with his sand sculpture on the New Year's Eve at Puri Beach in Odisha. (Image Credit: IANS)
Sand Artist Manas Sahoo bids adieu to 2017 and welcomes 2018 with his sand sculpture on the New Year's Eve at Puri Beach in Odisha. (Image Credit: IANS)
People watch fireworks celebrating the New Year in Rio De Janeiro, Brazil. (Image Credit: Xinhua/IANS)
People watch fireworks celebrating the New Year in Rio De Janeiro, Brazil. (Image Credit: Xinhua/IANS)
People fly lanterns at Borobudur temple in Indonesia's Magelang, during New Year celebrations. (Image Credit: Antara Foto Agency/Reuters)
People fly lanterns at Borobudur temple in Indonesia's Magelang, during New Year celebrations. (Image Credit: Antara Foto Agency/Reuters)

Revellers in Canada and the United States participated in New Year celebrations braving the cold. Although a number of events were cancelled in several Canadian cities due to extreme cold, crowds gathered at Montreal’s Old Port and Grande Allee in the Quebec City to bring in 2018, reported CBC News. Meanwhile, hundreds of thousands of people gathered at Times Square despite freezing temperatures to watch the 2018 ball drop and confetti rain.

Revelers in Times Square photographed ahead of New Year's celebrations in Manhattan, New York. (Image Credit: Darren Ornitz/Reuters)
Revelers in Times Square photographed ahead of New Year's celebrations in Manhattan, New York. (Image Credit: Darren Ornitz/Reuters)
A performer plays LED sticks during the New Year celebrations at Canada Place in Vancouver, Canada. (Image Credit: Xinhua/IANS)
A performer plays LED sticks during the New Year celebrations at Canada Place in Vancouver, Canada. (Image Credit: Xinhua/IANS)