It was - as Carlos Nuzman, president of the Rio Olympics and Paralympics organising committee, put it - a "mission of many doubts".

Yet, as the Paralympics drew to a close on Sunday - amid applause, song and dance at the closing ceremony - it was a case of mission accomplished for the organisers after 11 days of memorable sporting action for para-athletes.

They overcame Brazil's political and economic woes, health concerns over the Zika virus, as well as lingering tensions over a ban imposed on the entire Russian team because of alleged state doping, to successfully celebrate the human spirit of all the para-athletes.

International Paralympic Committee president Philip Craven recognised the warmth of the hosts, the first South American country to stage the quadrennial Games, and said in his closing speech: "Your vocal support has been even more beautiful than your stunning city.

"The noise you created, the passion you shared, the warmth you provided, inspired Paralympians to achieve what some thought impossible."

He announced that he will award the people of Rio and Brazil its last "medal" tomorrow - the Paralympic Order, which is the highest honour bestowed by the Paralympic movement.

In the course of the Games, the para-athletes competed with grace and at times jaw-dropping skills, as the organisers eventually sold 2.1 million tickets - fewer than London in 2012 but more than Beijing four years earlier.

Part of that success was due to many tickets being sold for as little as US$3 (S$4.08) - or given away to school children in an international fill-the-seats campaign.

The gap between the Olympics and Paralympics gradually blurred, with disabled athletes breaking a succession of records in Rio.

Among the stars were Brazil's swimmer Daniel Dias, who added four golds, three silvers and two bronzes to his existing medal haul from Beijing and London - which in turn won him repeated descriptions as the Michael Phelps of the Paralympics.

There was also amazement in the 1,500m track race when visually impaired Algerian Abdellatif Baka set a record that was more than 1.7 seconds faster than the winning time by Olympic gold medallist Matthew Centrowitz in the same stadium a month earlier.

However, Centrowitz won in what was by Olympic standards a near-record slow race, meaning Baka's outstanding time was of mostly symbolic significance.

For the fourth straight Games, China topped the medal standings. They captured 107 golds and 239 medals overall in South America, followed by Great Britain (64 golds) and Ukraine (41 golds).

Hosts Brazil fell short of their target of a top-five finish. They were eighth, with 14 gold, 29 silver and 29 bronze for a total of 72 medals.

Singapore sent a record 13-strong team to Brazil, its largest Paralympics contingent.

Para-swimmers Yip Pin Xiu and Theresa Goh won two golds and a bronze respectively as the Republic finished 46th in the rankings.

It was also the first time that a Singaporean had won multiple golds at the same Paralympics.

The only sombre moment of the closing ceremony was a tribute to Iranian cyclist Bahman Golbarnezhad, 48, who was killed in a road race crash on Saturday. It was the first-ever death of an athlete during the Games.

As per tradition, the Olympic flag was symbolically handed over to the next host nation, Tokyo, which will stage the 2020 Games.

Flags with the word "love" inscribed in various languages took over the centre of the stadium - where the Paralympians were seated - before a stunning fireworks show closed the party.