Ionic - Typescript error - Type is not an array or a string

I am starting with Ionic and Angular and I am facing an issue with variable type. I am querying an API that ouput an array of elements.

import { Component } from '@angular/core';
import { NavController } from 'ionic-angular';
import  {PostService } from '../_providers/post-service';

@Component({
  selector: 'page-home',
  templateUrl: 'home.html',
  providers:[PostService]
})
export class HomePage {
  public posts: any;
  private start:number=0;

  constructor(public navCtrl: NavController, public postService: PostService) {
    this.getPost();
  }
  getPost(){
    return new Promise(
      resolve => {
        this.postService.load(this.start)
        .then(data => {
          console.log(data);
          for(let post of data) {
            this.posts.push(post);
          }
          resolve(true);
        });
      });
}

  doInfinite(infiniteScroll:any) {
   console.log(this.start);
   this.start+=10;
   this.getPost().then(()=>{
       infiniteScroll.complete();
     });
 }

  likePost(post){
    post.likes++;
  }

}

Line 23, I have this issue: issue

And the console.log returns: console.log

Finally, the PostService class looks like this:

import { Injectable } from '@angular/core';
import { Http } from '@angular/http';
import 'rxjs/add/operator/map';

@Injectable()
export class PostService {

  perpage:number = 10;

  constructor(public http: Http) {}

  load(start:number=0) {

    return new Promise(resolve => {

      this.http.get('http://api.voyonsvoir.fr/?[limit]='+this.perpage+'&filter[skip]='+start)
        .map(res => res.json())
        .subscribe(data => {
          resolve(data.posts);

        });
    });
  }
}

Thanks for your help.