Backbone fetch (or sync) doesn't look up right url - backbone.js

Question

I'm trying to get some data from the node server, which works fine, but when I try to GET data via the Backbone fetch (or sync), the request fails. I noticed that, for some reason, actual request is wrong: 'GET http://localhost:3000/socket.io/1/' where it should be 'GET http://localhost:3000/cars', since '/cars' is the value of the URL field that Backbone uses by convention for these operations. These are the relevant modules:
var Backbone = require("backbone");
var Car = require('models/car');
var Cars = Backbone.Collection.extend ({
model: Car,
url: '/cars',
// Unselect all Car Cards
resetSelected: function() {
for (var i=1; i<=this.length; ++i) {
var carcard=this.get(i);
carcard.set({"selected": false});
console.log(carcard.attributes.name + ' unselected');
}
},
// Select a specific model from the collection
selectByID: function(id) {
this.resetSelected();
var carcard = this.get(id);
carcard.set({"selected": true});
console.log(carcard.attributes.name + " selected");
return carcard.attributes.id;
}
});
module.exports = Cars;
And a model:
var Backbone = require("backbone");
var Car = Backbone.Model.extend({
defaults: {
year: 2011,
brand: "Brand",
model: "Model",
name: "Car Name",
pictureFle: "img/car.jpg",
kmTraveled: 0,
litresSpent: 0,
selected: false
},
});
module.exports = Car;
I tried to populate the collection like this:
var cars = new Cars();
cars.fetch();
but, as I explained, failed. Any ideas what the problem could be?