[php] Laravel Unknown Column 'updated_at'

I've just started with Laravel and I get the following error:

Unknown column 'updated_at' insert into gebruikers (naam, wachtwoord, updated_at, created_at)

I know the error is from the timestamp column when you migrate a table but I'm not using the updated_at field. I used to use it when I followed the Laravel tutorial but now that I am making (or attempting to make) my own stuff. I get this error even though I don't use timestamps. I can't seem to find the place where it's being used. This is the code:

Controller

public function created()
{
    if (!User::isValidRegister(Input::all())) {
        return Redirect::back()->withInput()->withErrors(User::$errors);
    }

    // Register the new user or whatever.
    $user = new User;
    $user->naam = Input::get('naam');
    $user->wachtwoord = Hash::make(Input::get('password'));
    $user->save();

    return Redirect::to('/users');
}

Route

Route::get('created', 'UserController@created');

Model

public static $rules_register = [
    'naam' => 'unique:gebruikers,naam'
];

public static $errors;
protected $table = 'gebruikers';

public static function isValidRegister($data)
{
    $validation = Validator::make($data, static::$rules_register);

    if ($validation->passes()) {
        return true;
    }

    static::$errors = $validation->messages();

    return false;
}

I must be forgetting something... What am I doing wrong here?

For those who are using laravel 5 or above must use public modifier other wise it will throw an exception

Access level to App\yourModelName::$timestamps must be
public (as in class Illuminate\Database\Eloquent\Model)

public $timestamps = false;

Setting timestamps to false means you are going to lose both created_at and updated_at whereas you could set both of the keys in your model.

Case 1:

You have created_at column but not update_at you could simply set updated_at to false in your model

class ABC extends Model {

const UPDATED_AT = null;

Case 2:

You have both created_at and updated_at columns but with different column names

You could simply do:

class ABC extends Model {

const CREATED_AT = 'name_of_created_at_column';
const UPDATED_AT = 'name_of_updated_at_column';

Finally ignoring timestamps completely:

class ABC extends Model {

public $timestamps = false;

Nice answer by Alex and Sameer, but maybe just additional info on why is necessary to put

public $timestamps = false;

Timestamps are nicely explained on official Laravel page:

By default, Eloquent expects created_at and updated_at columns to exist on your >tables. If you do not wish to have these columns automatically managed by >Eloquent, set the $timestamps property on your model to false.