Leader of the '400 Mazowo' gang, Wilson Joseph alias Lanmò Sanjou (in English, Death Without Days), was seen giving the 'warnings' while speaking at a funeral Wednesday for gang members whom he alleges were killed by the Haitian police.

In a video posted on social media on Thursday, Wilson Joseph said, "I swear by thunder that if I don’t get what I’m asking for, I will put a bullet in the heads of these Americans."

Local authorities earlier said the gang has demanded $1 million ransom each for the 17 people, including 12 adults and five minors, it is holding.

File images of Haitian security forces carrying out ops against gang members, screengrabbed from Youtube

The missionaries, who worked for Ohio-based non-profit religious organization- Christian Aid Ministries- that supplies Haitian children with shelter, food and clothing, and their family members were abducted on Saturday evening when they were traveling by vehicle to Titanyen, north of the Port-au-Prince, after visiting Maison La Providence de Dieu orphanage in the Croix des Bouquets area.

Haiti's justice minister Liszt Quitel said the kidnappers have demanded $17 million ransom for the missionary group's release while the hostages, including 16 US citizens and one Canadian, along with their Haitian driver are reportedly being held somewhere outside the Croix-des-Bouquets suburb controlled by the gang.

Related article: Haiti gang demands $17M ransom for kidnapped American and Canadian missionaries

Officials having direct knowledge of the development said an investigation has been initiated into the matter amid ongoing negotiations with the kidnappers.

Earlier, CNN reported quoting Haitian justice minister Quitel that both the National Police negotiators and the United States' Federal Bureau of Investigation (FBI) were advising the missionary group on how to proceed amid ongoing negotiations, while FBI agents were on the ground in Haiti assisting with the investigation.

The FBI, which is part of a coordinated US government effort to get the Americans involved to safety, are not leading the negotiations and its agents on ground have not spoken directly with the kidnappers, Liszt Quitel told CNN days ago.

Haitian authorities and US investigators have denied sharing further information due to operational considerations.

Related article: Group of American missionaries kidnapped by gang members in Haiti

Haiti has one of the highest rates of kidnapping-for-ransom in the world, and since the assasination of President Jovenel Moïse on July 7, rival factions have been trying to gain control, resulting in a rapid increase in the rate of abduction amid lack of security in the country.

According to a report by the United Nations Integrated Office in Haiti (BINUH) issued last month, as many as 328 kidnapping victims were reported to the Caribbean  country's National Police in the first eight months of 2021 while the figure was at 234 for all of 2020.